• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.768-774
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• 2007

To study the effect of dietary docosahexaenoic acid (DHA) enrichment on the expression of hepatic genes in pigs, weaned, crossbred pigs (30 d old) were fed diets supplemented with either 2% tallow or DHA oil for 18 d. Hepatic mRNA was extracted. Suppression subtractive hybridization was used to explore the hepatic genes that were specifically regulated by dietary DHA enrichment. After subtraction, we observed 288 cDNA fragments differentially expressed in livers from pigs fed either 2% DHA oil or 2% tallow for 18 d. After differential screening, 7 genes were found to be differentially expressed. Serum amyloid A protein 2 (SAA2) was further investigated because of its role in lipid metabolism. Northern analysis indicated that hepatic SAA2 was upregulated by dietary DHA enrichment (p<0.05). In a second experiment, feeding 10% DHA oil for 2d significantly increased the expression of SAA2 (compared to the 10% tallow group; p<0.05). The porcine SAA2 full length cDNA sequence was cloned and the sequence was compared to the human and mouse sequences. The homology of the SAA2 amino acid sequence between pig and human was 73% and between pig and mouse was 62%. There was a considerable difference in SAA2 sequences among these species. Of particular note was a deletion of 8 amino acids, in the pig compared to the human. This fragment is a specific characteristic for the SAA subtype that involved in acute inflammation reaction. Similar to human and mouse, porcine SAA2 was highly expressed in the liver of pigs. It was not detectable in the skeletal muscle, heart muscle, spleen, kidney, lung, and adipose tissue. These data suggest that SAA2 may be involved in mediation of the function of dietary DHA in the liver of the pig, however, the mechanism is not yet clear.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.931-937
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• 2006

The full-length cDNA of the porcine SMPX gene was obtained by the rapid amplification of cDNA ends (RACE). The nucleotide sequences and the predicted protein sequences share high sequence identity with both human and mouse. The promoter of SMPX was sequenced and then analyzed to find the promoter binding sites. The reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that SMPX has a high level of expression in heart and skeletal muscle, a very low expression in lung and spleen and no expression in liver, kidney, fat and brain. Moreover, SMPX has a differential expression level in skeletal muscle, the expression in 65-day embryos being higher than other stages. The porcine SMPX was mapped to SSCXp24 by using a somatic cell hybrid panel (SCHP) and was found closely linked to SW1903 using the radiation hybrid panel IMpRH. An A/G single nucleotide polymorphism (PCR-RFLP) in the 3'-untranslated region (3'-UTR) was detected in eight breeds. The analysis of allele frequency distribution showed that introduced pig breeds (Duroc and Large White) have a higher frequency of allele A while in the Chinese indigenous pig breeds (Qingping pig, Lantang pig, YushanBlack pig, Large Black-White pig, Small Meishan) have a higher frequencies of allele G. The association analysis using an experimental population (188 pigs), which included two cross-bred groups and three pure-blood groups, suggested that the SNP genotype was associated with intramuscular fat content.

• Reproductive and Developmental Biology
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• v.37 no.4
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• pp.219-224
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• 2013

Muscular satellite cell (SC), which is stem cell of postnatal pig, is an important for study of differentiation into adipogenesis, myogenesis, and osteoblastogenesis. In this study, we isolated and examined from pig muscle tissue to determine capacity in proliferate, differentiate, and expression of various genes. Porcine satellite cells (PSC) were isolated from semimembranosus (SM) muscles of 90~100 days old pigs according to standard conditions. The cell proliferation increased in multi-potent cell by Masson's, oil red O, and Alizarin red staining respectively. We performed the expression levels of differentiation related genes using real-time PCR. We found that the differentiation into adipocyte increased expression levels of both fatty acid binding protein 4 (FABP4) and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) genes (p<0.01). Myocyte increased the expression levels of the myosin heavy chain (MHC), myogenic factor 5 (Myf5), myogenic regulatory factor (MyoD), and Myogenic factor 4 (myogenin) (p<0.01). Osteoblast increased the expression levels of alkaline phosphatase (ALP) (p<0.01). Finally, porcine satellite cells were induced to differentiate towards adipogenic, myogenic, and osteoblastogenic lineages. Our results suggest that muscle satellite cell in porcine may influence cell fate. Understanding the progression of PSC may lead to improved strategies for augmenting meat quality.

• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.447-458
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• 1995

This study was carried out to characterize nonadrenergic, noncholinergic(NANC) relaxation of porcine retractor penis(PRP) muscle induced by electrical field stimulation(EFS) and to investigate the actions of niric oxide(NO) and vasoactive intestinal polypeptide(VIP) as candidates for NANC neurotransmitters. Biphasic relaxations of PRP muscle were induced by EFS to NANC nerve. Rapid-phase relaxation was observed at low frequency(0.5-16Hz) and slow-phase relaxation followed during high frequency(8-60Hz). Both relaxations were frequency-dependent and TTX($1{\times}10^{-6}M$)-sensitive. L-NAME($2{\times}10^{-5}M$) inhibited the rapid-phase relaxation, but not the slow-phase relaxation. The inhibition of the rapid-phase relaxation with L-NAME was reversed by L-arginine ($1{\times}10^{-3}M$) but not by D-arginine($1{\times}10^{-3}M$). Methylene blue($4{\times}10^{-5}M$) reduced the rapid-phase relaxation. Exogenous No(ExoNO, $1{\times}10^{-5}-1{\times}10^{-4}M$) induced dose-dependent relaxations of PRP muscle. Oxyhemoglobin($5{\times}1^{-5}M$) blocked the relaxation induced by ExoNO and inhibited EFS-induced relaxation. Hydroquinone($1{\times}10^{-4}M$) also abolished the relaxation induced by ExoNO, but did not affect EFS-induced relaxation. L-NAME resistant slow-phase relaxation to EFS was inhibited by ${\alpha}$-chymotrypsin(2.5 U/ml). Both methylene blue($4{\times}10^{-5}M$) and Nethylmaleimide($1{\times}10^{-4}M$) reduced the slow-phase relaxation by EFS. [4-Cl-D-$Phe^6$, $Leu^{17}$]-VIP($3{\times}10^{-6}M$) inhibited the slow-phase relaxation by EFS. External applications of VIP ($1{\times}10^{-7}M$) caused relaxations that were simillar to the L-NAME resistant slow-phase relaxations induced by EFS, and relaxant effects of exogenous VIP were blocked by ${\alpha}$-chymotrypsin(2.5 U/ml).

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.173-179
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• 1989

The influence of the storage temperature and time after slaughter on the thermal denaturation of PSE porcine muscle protein was studied by differential scanning calorimetry and by measuring the solubility of the sarcoplasmic proteins. In the DSC therodiagram a decrease of the endotherm enthalpy of the myosin plus sarcoplasmic proteins in PSE muscle could be observed with an increase in the storage temperature and time of post mortem. Storage temperature at $20^{\circ}C$ during the first four hours of post mortem resulted in relatively slight denaturation of myosin plus sarcoplasmic proteins in PSE muscle. Storage temperature above $25^{\circ}C$ caused to increase the denaturation of muscle proteins. The minimal drip loss in PSE muscle could be observed, when the muscle was cooled to $2^{\circ}C$ as quickly as possible post mortem. However, when stored for several hours of post morte at a temperature between $32^{\circ}C-38^{\circ}C$, the drip loss reached the level established for PSE muscle. The paleness of PSE muscle could be prevented to some extent by rapid chill to $20^{\circ}C$ post mortem. The more the muscle proteins in the PSE muscle become denatured during the early storage period of post mortem, the more the drip loss increases. With the increase in the denaturation of myosin plus sarcoplasmic proteins in PSE muscle with regard to temperature of post mortem, there was a corresponding decrease in the solubility of the sarcoplasmic proteins in PSE muscle.

• Korean Journal of Veterinary Service
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• v.18 no.2
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• pp.177-181
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• 1995

The effects of histamine were investigated on the uterine smooth muscle motility in the pig. The results were summarized as fellows : 1. Histamine caused the contraction of the porcine uterine smooth muscle and the contractile responses increased between the concetration of histamine $10^{-8}$ and $10^{-5}$ M with a dose-dependent manner. 2. The contractile response Induced by histamine ($10^{-6}$ M) was completely blocked by pretrevatment with $H_1$-histaminergic receptor blocker, pyrilamine($10^{-6}$ M) 3. The contractile response induced by histamine($10^{-6}$ M) was increased by pretreatment with $H_2$-histaminergic receptor blocker, cimetidine($10^{-6}$ M) From these results, it was concluded that the effects of uterine smooth muscle by histamine were the contraction mediated by $H_1$-histaminergic receptor and the relaxation mediated by $H_2$-histaminergic receptor in pig.

• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.459-469
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• 1995

As S-nitrosothiols were proposed as nitrergic carriers in vascular and nonvascular smooth muscle, we have investigated the relaxant properties of several S-nitrosothiols in the porcine retractor penis(PRP) muscle and compared them with the effects of exogenously added NO, electrical field stimulation(EFS) of NANC nerves and sodium nitroprusside(SNP). Also the influences of oxyhemoglobin and hydroquinone on the relaxant responses were investigated. In addition, effects of NO on membrane potentials and its involvement in the generation of inhibitory junction potential(IJP) were investigated with conventional intracellular microelectrode technique. The results were summerized as follows. 1. Frequency-dependent relaxations of PRP muscle were induced by EFS to NANC nerve. Tetrodotoxin($1{\times}10^{-6}M$) abolished the relaxations of PRP muscle induced by EFS, and L-NAME(($2{\times}10^{-5}M$) and methylene blue($4{\times}10^{-5}M$) inhibited the relaxations. L-NAME-induced inhibition of the relaxations was reversed by L-arginine($1{\times}10^{-3}M$), but not by D-arginine. 2. Exogenous NO($1{\times}10^{-5}-1{\times}10^{-4}M$), sodium nitroprusside(($1{\times}10^{-7}-1{\times}10^{-4}M$) induced dose-dependent relaxations of PRP muscle. All S-nitrosothiols($1{\times}10^{-7}-1{\times}10^{-4}M$) tested relaxed the PRP muscle in dose-dependent manner and the potency order was SNAP>GSNO>CysNO>SNAC. 3. Oxyhemoglobin($5{\times}10^{-5}M$) blocked the relaxation induced by exogenous NO and inhibited EFS-, S-nitrosothiols-, and SNP-induced relaxation. 4. Hydroquinone($1{\times}10^{-4}M$) also abolished the relaxations induced by exogenous NO, and reduced the relaxations induced by S-nitrosothiols, but did not affect EFS- and SNP-induced relaxations. 5. SNP($2{\times}10^{-6}-5{\times}10^{-6}M$) relaxed muscle strips but the membrane potentials were not affected. 6. EFS with several pulses(1ms, 2Hz, 80V) produced an inhibitory junction potential(IJP) with muscle relaxation. They were abolished by TTX($2{\times}10^{-6}M$). $N^G$-nitro-$_{\small{L}}$-arginine(L-NNA, $2{\times}10^{-5}M$) abolished the muscle relaxation, but had no effect on IJP.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.8
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• pp.1134-1142
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• 2008

Cationic amino acid transporter $b^{0,+}AT$ (HGMW-approved gene symbol SLC7A9, solute carrier family 7, member 9) plays a crucial role in amino acid nutrition. In the present study, we describe the cloning and sequencing of porcine $b^{0,+}AT$. Based on the sequence of porcine $b^{0,+}AT$ deposited in the NCBI (National Center for Biotechnological Information), we identified a putative porcine homologue. Using rapid amplification of cDNA ends (RACE), the full-length cDNA encoding porcine $b^{0,+}AT$ was isolated. The porcine $b^{0,+}AT$ cDNA was 1,680 bp long, encoding a 487 amino acid trans-membrane protein. The predicted amino acid sequence was found to have 88.9% and 87.1% identity with human and mouse $b^{0,+}AT$, respectively. Real-time RT-PCR indicated porcine $b^{0,+}AT$ transcripts expressed in heart, kidney, muscle and small intestine. The small intestine had the highest $b^{0,+}AT$ mRNA abundance while the muscle had the lowest (p<0.05). Along the longitudinal axis, the ileum had the highest $b^{0,+}AT$ mRNA abundance while the colon had the lowest (p<0.05). The $b^{0,+}AT$ mRNA level was highest on day 7 and 90 in the duodenum (p<0.05). It increased from day 1 to day 26 in the jejunum (p>0.05) and had the highest abundance on day 60 (p<0.05). There was, however, no difference between day 1, 7, 26, 30, 90 and 150 (p>0.05). The strongest $b^{0,+}AT$ expression appeared on day 7 in the ileum before weaning, and then decreased till day 30 but rose gradually again from day 60 to 150 (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.897-902
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• 2004

PSMC5 subunit, which belongs to the 26S proteasomal subunit family, plays an important role in the antigen presentation mediated by MHC class I molecular. Full-length cDNA of porcine PSMC5 was isolated using the in silico cloning and rapid amplification of cDNA ends (RACE). Amino acid was deduced and the primary structure was analyzed. Results revealed that the porcine PSMC5 gene shares the high degree of sequence similarity with its mammalian counterparts at both the nucleotide level and the amino acid level. The RT-PCR was performed to detect the porcine PSMC5 expression pattern in seven tissues and the result showed that high express level was observed in spleen, lung, marrow and liver while the low express level was in muscle. The full-length genomic DNA sequence of porcine PSMC5 gene was amplified by PCR and the genomic structure revealed that this gene was comprised by 12 exons and 11 introns. Best alignment of the cDNA and genomic exon DNA sequence presents 4 mismatches and this information potentially bears further study in gene polymorphisms.

• Food Science of Animal Resources
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• v.39 no.2
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• pp.229-239
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• 2019

The objectives of this study were to determine the interaction between porcine myofibrillar proteins and various gelatins (bovine hide, porcine skin, fish skin, and duck skin gelatins) and their impacts on gel properties of porcine myofibrillar proteins. Porcine myofibrillar protein was isolated from pork loin muscle (M. longissimus dorsi thoracis et lumborum). Control was prepared with only myofibrillar protein (60 mg/mL), and gelatin treatments were formulated with myofibrillar protein and each gelatin (9:1) at the same protein concentration. The myofibrillar protein-gelatin mixtures were heated from $10^{\circ}C$ to $75^{\circ}C$ ($2^{\circ}C/min$). Little to no impacts of gelatin addition on pH value and color characteristics of heat-induced myofibrillar protein gels were observed (p>0.05). The addition of gelatin slightly decreased cooking yield of heat-induced myofibrillar protein gels, but the gels showed lower centrifugal weight loss compared to control (p<0.05). The addition of gelatin significantly decreased hardness, cohesiveness, gumminess, and chewiness of heat-induced myofibrillar gels. Further, sodium dodecyl poly-acrylamide gel electrophoresis (SDS-PAGE) showed no interaction between myofibrillar proteins and gelatin under non-thermal conditions. Only a slight change in the endothermic peak (probably myosin) of myofibrillar protein-gelatin mixtures was found. The results of this study show that the addition of gelatin attenuated the water-holding capacity and textural properties of heat-induced myofibrillar protein gel. Thus, it could be suggested that well-known positive impacts of gelatin on quality characteristics of processed meat products may be largely affected by the functional properties of gelatin per se, rather than its interaction with myofibrillar proteins.