Biomedical subjects

H Takahara

Publications and source records attributed to H Takahara.

At least 19 recordsLinked to original sources

PubMed2001

Palaeovegetation. Diversity of temperate plants in east Asia.

The exceptionally broad species diversity of vascular plant genera in east Asian temperate forests, compared with their sister taxa in North America, has been attributed to the greater climatic diversity of east Asia, combined with opportunities for allopatric speciation afforded by repeated fragmentation and coalescence of populations through Late Cenozoic ice-age cycles. According to Qian and Ricklefs, these opportunities occurred in east Asia because temperate forests extended across the continental shelf to link populations in China, Korea and Japan during glacial periods, whereas higher sea levels during interglacial periods isolated these regions and warmer temperatures restricted temperate taxa to disjunct refuges. However, palaeovegetation data from east Asia show that temperate forests were considerably less extensive than today during the Last Glacial Maximum, calling into question the coalescence of tree populations required by the hypothesis of Qian and Ricklefs.

Biological Evolution↗

PubMed2001

Water-soluble and water-insoluble glucans produced by Escherichia coli recombinant dextransucrases from Leuconostoc mesenteroides NRRL B-512F.

Two dextransucrase genes, dsrS and dsrT5, from Leuconostoc mesenteroides NRRL B-512F were expressed in Escherichia coli, and recombinant dsrT5 dextransucrase was shown to produce a water-insoluble glucan. In contrast, native dextran from L. mesenteroides B-512F is water-soluble. The water-insoluble glucan was shown by 13C NMR and glycosyl-linkage composition analysis to contain about 50% 6-linked Glcp and 40% 3-linked Glcp. The 'primitive' B-512F strain is suggested to have produced water-insoluble glucan containing 3-linked Glcp. The glucans produced by dextransucrases expressed in E. coli contained 4-linked Glcp, as shown by glycosyl-linkage composition analysis. The amount of 4-linked Glcp was increased when the truncated, water-insoluble, glucan-producing dextransucrase, which does not have C-terminal repeating units, was added to the water-soluble, glucan-producing dextransucrase. Trace amounts of 4-linked Glcp were also detected in the dextran obtained from the B-512F culture supernatant, in dextran produced by dextransucrase purified from the B-512F strain culture supernatant, and in clinical dextran. The results of glycosyl-linkage composition analysis suggest that dextransucrases produce 4-linked Glcp as well as 6- and 3-linked Glcp.

Escherichia coli↗

PubMed2001

Immunoreactive relaxin in seminal plasma of fertile boars and its correlation with sperm motility characteristics determined by computer-assisted digital image analysis.

Ejaculates from 10 mature fertile large white Yorkshire boars were used to examine the correlation between immunoreactive relaxin levels in seminal plasma and sperm motility characteristics. Seminal plasma levels of immunoreactive relaxin were measured by a time-resolved fluoroimmunoassay (TR-FIA). Motility characteristics were assessed using a CellSoft computer-assisted digital image analysis system. The mean +/- SD level of immunoreactive relaxin in seminal plasma was 2.61 +/- 0.62 ng/mL. When the correlation between seminal plasma levels of immunoreactive relaxin and parameters of sperm movement was examined, it was found that relaxin levels were significantly correlated with the percentage of motile spermatozoa (r=0.687, p < 0.05), curvilinear velocity (r=0.745, p < 0.05), straight line velocity (r=0.651, p < 0.05), mean amplitude of lateral head displacement (mean ALH) (r=0.844, p < 0.01) and the maximum amplitude of lateral head displacement (max ALH) (r=0.830, p < 0.01), but not with linearity, beat-cross frequency, or percentage of circular cells. Among these parameters, seminal plasma levels of immunoreactive relaxin showed the strongest correlation with the ALH parameter related to fertilizing ability. These results indicate that immunoreactive relaxin in boar semen may be necessary not only for normal sperm motility but also for normal fertility, suggesting that determination of the profile of immunoreactive relaxin in ejaculates may have value as a potential marker for predicting sperm fertilizing ability of boars.

Animals↗

PubMed2001

Human vascular smooth muscle cells of diabetic origin exhibit increased proliferation, adhesion, and migration.

PURPOSE: Patients with diabetes mellitus (DM) experience progressive macrovascular atherosclerosis and intimal hyperplastic restenosis with increased frequency as compared with nondiabetic patients. These observations suggest that vascular smooth muscle cells (VSMCs) behave in a phenotypically different and more aggressive manner in diabetic patients. In this study, we compared the in vitro rates of proliferation, adhesion, and migration of human VSMCs obtained from diabetic and nondiabetic patients. METHODS: Human VSMC cultures were isolated from 23 diabetic patients (9 artery, 14 vein) and 15 nondiabetic patients (9 artery, 6 vein) with extensive lower extremity atherosclerosis. All patients were between 61 and 78 years of age (average: 68.4 years [diabetic]; 67.3 years [nondiabetic]). All diabetic patients had type 2 DM. Vascular specimens were obtained at the time of amputation from infragenicular arteries and during arterial revascularization from saphenous veins. Cells from passages 2 and 3 were assayed for their proliferative capacity with total DNA fluorescence photometry and for adhesion and migration with a modified Boyden chamber. RESULTS: The average duration of diabetes was 11.6 +/- 4.1 years. The average number of diabetic complications (retinopathy, neuropathy, nephropathy, coronary artery disease) was 2.8 +/- 0.7 per patient. Diabetic VSMCs exhibited abnormal morphology in cell culture with loss of the normal hill and valley configuration. Proliferation was significantly increased in VSMCs of diabetic origin (156 +/- 57 absorption units) as compared with those of nondiabetic origin (116 +/- 42 absorption units) (P <.001). Diabetic VSMCs demonstrated significantly greater adhesion (63.6 +/- 24 per high-power field vs 37.9 +/- 13 per high-power field; P =.002) and migration (397 +/- 151 per low-power field vs 121 +/- 99 per low-power field; P =.001) rates. CONCLUSIONS: Diabetic VSMCs exhibit significantly increased rates of proliferation, adhesion, and migration as well as abnormal cell culture morphology suggestive of abnormal contact inhibition. These observations of human VSMCs in culture are consistent with the increased rate of infragenicular atherosclerosis and the increased rates of restenosis observed clinically in diabetic patients. The atherosclerosis- and intimal hyperplasia-promoting behavior exhibited appears to be intrinsic to the DM-VSMC phenotype and must be considered when designing methods to limit atherosclerosis and intimal hyperplasia in diabetic patients.

Aged↗

PubMed2001

Changes in serotonin levels and 5-HT receptor activity in duodenum of streptozotocin-diabetic rats.

Few previous studies have discussed the changes in serotonin receptor activity in the small intestine of diabetic animals. Therefore, we examined serotonin content in duodenal tissue and dose-dependent effects of serotonin agonists and antagonists on the motor activity of ex vivo vascularly perfused duodenum of streptozotocin (STZ)-diabetic rats. Serotonin content was significantly increased in enterochromaffin cells but not altered in serotonin-containing neurons in STZ-diabetic rats. Motor activity assessed by frequency, amplitude, and percent motility index per 10 min of pressure waves was reduced in the duodenum of diabetic rats, and this reduction was reversed by insulin treatment. Serotonin dose dependently increased the motor activity in control rat duodenum but only a higher concentration of serotonin increased the motor activity in diabetic rats. The 5-hydroxytryptamine (5-HT) receptor subtype 4 (5-HT(4)) antagonist SB-204070 dose dependently reduced motor activity in both control and diabetic rats, whereas the 5-HT(3) receptor antagonist azasetron, even at a higher concentration, failed to affect motor activity in diabetic rat duodenum but dose dependently reduced motor activity in control rat duodenum. These results suggest that 5-HT(3) receptor activity was impaired but 5-HT(4) receptor activity was intact in STZ-diabetic rat duodenum. Such an impairment of 5-HT(3) receptor activity may induce the motility disturbance in the small intestine of diabetes mellitus.

Animals↗

PubMed2001

Ingestion of gelatin has differential effect on bone mineral density and body weight in protein undernutrition.

Malnutrition, particularly protein undernutrition, contributes to the occurrence of osteoporotic fracture by lowering bone mass. In this study, the effects of dietary protein on bone mineral density and body weight in protein undernutrition were compared between gelatin and milk casein. When mice were fed for 10 wk with a low protein diet containing 10(%) casein or 6% casein +4% gelatin, there was no significant difference in the final body weight between the 6% casein+4% gelatin group and the 10% casein group. In contrast, bone mineral content and bone mineral density of the femur were significantly higher in the 6% casein+4% gelatin group than in the 10% casein group. Bone mineral content and bone mineral density did not differ significantly in 14% protein groups between 14% casein and 6% casein +80% gelatin. These results suggest that gelatin has differential effects on bone mineral density and body weight in protein undernutrition.

Animals↗

PubMed2000

Identification of N(omega)-carboxymethylarginine as a novel acid-labileadvanced glycation end product in collagen.

Collagen undergoes continuous non-enzymatic glycation during its long life period. The products resulting from the glycation reaction, so-called advanced glycation end products (AGEs), were regarded as potential pathogens of various diseases such as diabetic complications. Although several AGEs were identified from acid hydrolysates of glycated collagen, the major AGE(s) responsible for the diseases have not yet been fully characterized. Moreover, acid-labile constituents were decomposed during acid hydrolysis. To investigate these AGEs, we used the enzymatic hydrolysis method [Bensusan, Dixit and McKnight (1971) Biochim. Biophys. Acta 251, 100-108]. As a result, an acid-labile unknown compound was discovered from the digested glycated collagen. We identified this compound as N(omega)-carboxymethylarginine (CMA) by matrix-assisted laster-desorption ionization-MS and NMR. CMA gradually increased in collagen during incubation with glucose and the yield reached about 8 mol/mol of collagen, which is 100 times higher than that of pentosidine. This result suggests that CMA is a major AGE in collagen.

Arginine↗

PubMed2000

[The C tube in biliary surgery--its development and clinical application].

BACKGROUND: The T tube procedure for bile drainage after biliary surgery has been used all over the world for more than 90 years. However, this method has serious drawbacks: a high complication ratio and a need for long-term hospitalization. Therefore other bile drainage methods including PTGBD, PTBD and ENBD have been developed, but none has so far been able to replace T tube. We have developed a new technique for bile drainage using the C tube (cystic duct tube), which is a slender tube (6Fr. polyvinyl) inserted via the cystic duct into the common bile duct (CBD). We have used C tube in more than 400 cases over the last 20 years: for open surgery during the first 10 years, and for laparoscopic surgery in the last 10 years. Here we describe the history of improvements in the C tube method and the techniques of C tube application in biliary surgery. Elastic surgical suture has been used to fix the C tube to the cystic duct, which successfully prevented bile leakage from the ductal stump after withdrawal of the tube. C tube is not only used for postoperative bile drainage but also for the management of remnant stones. The purpose of this study is to assess the safety and benefits of the C tube procedure. METHODS: I: From 1980 to 1998, 335 cholecystectomized cases which had undergone the C tube procedure were examined for complications resulting from C tube placement. II: We analyzed 134 patients with choledocholithiasis: 34 patients had been treated using C tube drainage, and 100 patients had been treated with the T tube procedure after undergoing CBD exploration. The main outcome criteria were: the frequency of post-operative complications, quantity of bile drainage, drainage period, and length of post-operative hospital stay. III: Between 1990 and 1999, 131 patients (15.2%) of a total of 860 laparoscopically cholecystectomized patients with gallstones underwent C tube treatment. We assessed the usefulness of the C tube procedure for the detection and management of remnant stones. RESULTS: I: There were no major complications (bile-leakage, CBD stenosis, etc.) in 335 cases which underwent the C tube procedure. Minor complications related to C tube were: spontaneous withdrawal of the tube in 5 cases, movement of the tube tip in 17 cases, and difficulties during tube removal in 32 cases which included slight resistance. Two cases had liver dysfunction (GOT 705 IU/l and 488 IU/l), although this was easily normalized after withdrawal of the tube tip from the duodenal papillae into the CBD. II: The frequency of complications in patients who underwent the C tube procedure was zero, whilst in the T tube group the major complication rate was 3% and the minor complication rate was 21%. The quantity of bile drainage was 283.6 +/- 22.9 ml/day in the C tube group compared with 302.7 +/- 10.3 ml/day in the T tube group, showing no significant difference. The drainage period (5.9 +/- 0.6 days) in the C tube group was significantly shorter than in the T tube group (27.7 +/- 0.9 days). Hospital stays (11.6 +/- 0.6 days) in the C tube group were significantly shorter than in the T tube group (45.0 +/- 1.5 days). III: Remnant CBD stones were detected by postoperative cholangiography via the C tube in 28 (21.4%) of the C tube replacement cases and in 3.3% of all the laparoscopically cholecystectomized patients. Seventeen patients with remnant stones were managed using glyceryl trinitrate CBD perfusion-induced relaxation of the sphincter of Oddi. The remaining patients were managed with endoscopic papillary balloon dilatation (EPBD) and/or endoscopic sphincterotomy (EST) without reoperation. We also have described other applications of the C tube procedure for the evaluation of sphincter of Oddi motility as an indication for EST, for bile drainage in liver resection, in the treatment of liver injuries, and for duodenal decompression after duodenal surgery. Finally we have mentioned the possibility of C tube application in the management of obstructive jaundice and bile drainage in liver transplantation surgery. CONCLUSION: The C tube method in biliary surgery is safe and useful in comparison with the T tube method. We are strongly convinced that the T tube will be completely replaced by the C tube.

Aged↗

PubMed2000

Precursor of rat epidermal cathepsin L: purification and immunohistochemical localization.

Immunoblot study using anti-rat cathepsin L antibody revealed almost only a precursor present in a crude extract of homogenized lower epidermis of rat skin, while the precursor and mature form were detected in the upper epidermis. To elucidate mechanisms of synthesis of cathepsin L, we have purified a precursor of cathepsin L from rat epidermis and investigated its localization in the skin. The precursor was purified after separation from the mature form in the final purification step of active fraction for N-benzyloxycarbonyl-L-phenylalanyl-L-arginine-7-amido-4-methylcoumari n. The precursor showed a single protein band with Mr 39 kDa on SDS/polyacrylamide gel electrophoresis and was immunoreacted with the anti-rat cathepsin L antibody. Two types of NH(2)-terminal sequences obtained were identical to the amino acid residues from -96 to -86 and those from -93 to -87 deduced from cDNA of the precursor of cathepsin L. The precursor was processed to mature form of the enzyme and the enzyme activity remarkably increased after 48-h incubation of the whole epidermis in 1 M acetate buffer (pH 3. 5) at 20 degrees C. In histological sections of the skin, a thin and diffuse staining pattern was present in the spinous layer and a dense and linear staining in the granular layer of the epidermis. In contrast, rat liver showed more mature form than the precursor by immunohistological findings. These results suggest that cathepsin L may have some roles in the terminal differentiation.

Amino Acid Sequence↗

PubMed2000

Human peptidylarginine deiminase type III: molecular cloning and nucleotide sequence of the cDNA, properties of the recombinant enzyme, and immunohistochemical localization in human skin.

Peptidylarginine deiminase catalyzes the post-translational modification of proteins through the conversion of arginine to citrulline in the presence of calcium ions. In rodents, peptidylarginine deiminase has been classified into four isoforms, types I, II, III, and IV, which are distinct in their molecular weights, substrate specificities, and tissue localization. Of these isoforms, only type III was detected in epidermis and hair follicles. Although the role of this enzyme in these tissues is not yet clear, indirect data have shown that several structural proteins such as filaggrin, trichohyalin, and keratin are substrates for peptidylarginine deiminase. In this study, we cloned the full-length cDNA of human peptidylarginine deiminase type III (3142 bp) from cultured human keratinocytes by reverse transcription-polymerase chain reaction and by rapid amplification of cDNA ends methods. This cDNA contained a 1995 bp open reading frame encoding 664 amino acids (Mr = 74 770). To explore the physicochemical and enzymatic properties of human peptidylarginine deiminase type III, we constructed a plasmid for producing a recombinant human peptidylarginine deiminase type III in bacteria. The enzymatic characteristics of the recombinant enzyme were very similar to those of the rodent peptidylarginine deiminase type III. The recombinant enzyme showed the catalytic activities toward structural proteins of epidermis and hair follicle, filaggrin and trichohyalin, in which the deiminations maxima of about 60% and 13% arginine residues were observed in filaggrin and trichohyalin, respectively. An immunohistochemical study of human scalp skin with a monospecific anti-peptidyl-arginine deiminase type III antibody revealed that the type III enzyme was localized to the inner root sheath and outer root sheath of hair follicles. Peptidylarginine deiminase type III in the inner root sheath was notable between supramatrix and keratogenous zone and was scarcely detected in cornified hair zone. The enzyme was also expressed in the cuticle layer of hair. On the other hand, expression of the enzyme in the epidermis was very low. These data imply that human peptidylarginine deiminase type III is the predominant isoform in hair follicles and may function as a modulator of hair structural proteins, including trichohyalin during hair and hair follicle formation.

Amino Acid Sequence↗

PubMed2000

Gene encoding a dextransucrase-like protein in Leuconostoc mesenteroides NRRL B-512F.

A gene, dsrT, encoding a dextransucrase-like protein was isolated from the genomic DNA libraries of Leuconostoc mesenteroides NRRL B-512F dextransucrase-like gene. The gene was similar to the intact open reading frames of the dextransucrase gene dsrS of L. mesenteroides NRRL B-512F, dextransucrase genes of strain NRRL B-1299 and streptococcal glucosyltransferase genes, but was truncated after the catalytic domain, apparently by the deletion of five nucleotides. dsrT mRNA was produced in this strain L. mesenteroides when cells were grown in a sucrose medum, but at a level of 20% of that of dsrS mRNA. The molecular weight of the dsrT gene product was 150,000 by SDS-PAGE. The product did not synthesize dextran, but had weak sucrose cleaving activity. The insertion of five nucleotides at the putative deletion point in dsrT resulted in an enzyme with a molecular weight of 210,000 and with dextransucrase activity.

Amino Acid Sequence↗

PubMed1999

Aggregation of Egg-Lecithin Vesicles Induced by Iron(III) Chloride.

Aggregation behaviors of egg-lecithin vesicles were investigated. The crowded vesicle solution exhibited an irregular aggregation style in the presence of FeCl3. The process was composed of an induction period (2-5 days) and a sedimentation process ( approximately 12 h). The vesicles were stabilized by the positively charged species such as [(H2O)4Fe(OH)2 Fe(H2O)4]4+ in the induction periods. However, after the stationary state, the vesicles began to coagulate due to the transformation of the iron species into the inactive one. The existence of such time-lag for the aggregation to occur was mainly induced by the transient nature of iron(III) in the aqueous solution. Copyright 1999 Academic Press.

Journal Article↗

PubMed1999

Alginate oligosaccharides stimulate VEGF-mediated growth and migration of human endothelial cells.

Alginate oligosaccharides cleaved from alginic acid polysaccharides of seaweed were tested to determine their ability to enhance proliferation and migration of human umbilical vein endothelial cells. A mixture of alginate oligosaccharides (5 microg/ml in culture broth) stimulated endothelial cell growth, [(3)H]thymidine uptake and migration in the presence of recombinant vascular endothelial growth factor 165 (VEGF(165)). In contrast, a high concentration mixture of the oligosaccharides ( approximately 100 microg/ml) suppressed cell growth. The stimulatory activity was comparable to that of heparin, with affinity to VEGF(165), and decreased on heparin-induced stimulation. Each effective oligosaccharide had guluronic acid at the reducing end. A mixture of alginate oligosaccharides (5 microg/ml) and the most paragraph signeffective fraction (1 microg/ml) stimulated endothelial cell migration. In the presence of VEGF and heparin, some alginate oligosaccharides with the peripheral guluronic acid demonstrated marked stimulatory effects, and one fraction also showed a migratory effect. These findings indicate novel activities of alginate oligosaccharide(s) in endothelial cell growth and migration and suggest synergistic and/or stabilizing effects on VEGF(165)-dependent stimulation of endothelial cells.

Alginates↗

PubMed1999

Neurotransmitter release from the medial hyperstriatum ventrale of the chick forebrain accompanying filial imprinting behavior, measured by in vivo microdialysis.

The imprinting behavior of chicks was quantified as a preference score (correct response ratio) achieved in a running wheel apparatus. A total of 249 chicks were exposed to an imprinting stimulus and tested for stimulus-approaching behavior. The chicks were then classified as good learners (imprinted), poor learners (non-imprinted) and a gray-zone group, those were 46%, 31% and 23% of the total chicks respectively. Using the classified chicks, the acetylcholine (ACh) and glutamate releases from the medial hyperstriatum ventrale (MHV) of the chick forebrains were determined by in vivo microdialysis. The non-imprinted chicks were used as yoked controls. Increases of ACh and glutamate released were observed in the imprinted chicks during exposure to the imprinting stimulus, whereas there were no changes in the release of these neurotransmitters in the non-imprinted chicks during the imprinting exposure. These results might be indicated that cholinergic and glutamatergic synapses which are newly formed as functioning synapses with imprinting stimulus in the MHV are involved in the performance of imprinting behavior.

Acetylcholine↗

PubMed1999

Molecular cloning of cDNAs of mouse peptidylarginine deiminase type I, type III and type IV, and the expression pattern of type I in mouse.

Peptidylarginine deiminases (PADs), a group of post-translational enzymes, catalyze the conversion of protein-bound arginine residues to citrulline residues in a calcium ion-dependent manner and are widely distributed in various organs of vertebrates. Although the existence of four isoforms of PAD (types I, II, III, and IV) is reported in rodents, the relative functions of the isoforms with respect to their colocation in the tissues have yet to be explored. In this study, we cloned the full-length cDNA encoding mouse PAD type I by screening a uterine cDNA library and using the RACE method. This cDNA consists of an open reading frame of 1989 bases encoding 662 amino acids (73,823 Da), a 5'-untranslated region of 127 bases and a 3'-untranslated region of 1639 bases. Comparative reverse transcription-PCR and Northern-blot analyses detected PAD type I mRNA only in the epidermis and uterus. Administration of estrogen to adult ovariectomized mice increased the content of PAD type I mRNA in the uterus, providing evidence that its expression is under the control of the sex steroid hormone. We also cloned the full-length cDNAs of mouse PAD type III and type IV by the reverse transcription-PCR and RACE methods. The primary structure of PAD type III contains 664 amino acids (75,098 Da) deduced from the coding region of 1995 bases, and the primary structure of PAD type IV consists of 666 amino acids (74,475 Da) deduced from the coding region of 2001 bases. Comparison of the deduced amino acid sequences of all four isoforms of PAD showed about 50% identity with each other, the 3' regions being highly homologous compared with the 5' regions.

Amino Acid Sequence↗

PubMed1998

Cloning of cDNA encoding a novel isoform (type IV) of peptidylarginine deiminase from rat epidermis.

We isolated a new clone that showed structural similarities with the rat peptidylarginine deiminase (PAD) types II and III. The full-length cDNA sequence of this novel PAD comprised 1998 bp encoding a sequence for 666 amino acid residues (Mr 74467), a 3'-non-coding region of 115 bp and a 5'-non-coding region of 16 bp. The derived amino acid sequence of the PAD showed 51.1 and 54.0% identities with the sequences of types II and III, respectively. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assays of mRNAs from several tissues of rat indicated that the PAD message is highly expressed in the pancreas, spleen, and ovary and, less strongly expressed in the liver, lung, stomach, kidney, uterus, and dermis, and weakly expressed in the brain, heart and epidermis. Since this expression pattern was quite different from those of the previously reported PAD types I, II, and III, we designated this novel PAD as type IV.

Amino Acid Sequence↗

PubMed1997

Stimulation of human keratinocyte growth by alginate oligosaccharides, a possible co-factor for epidermal growth factor in cell culture.

Oligosaccharides, involved in regulation of plant developmental and defensive processes, were tested to determine their ability to enhance proliferation of human keratinocytes. A mixture of alginate oligosaccharides remarkably stimulated keratinocyte growth and [3H]thymidine uptake in the presence of epidermal growth factor (EGF). The activity was comparable to bovine pituitary extract, a common complement in keratinocyte culture, and additive on BPE-induced stimulation. The most effective oligosaccharide in the mixture was identified and its chemical structure was determined. These findings demonstrate a novel activity of alginate oligosaccharide(s) in keratinocyte growth and suggest a possible co-factor for EGF-dependent stimulation in medium for keratinocytes.

Alginates↗

PubMed1997

Comparative studies on the histochemical properties of M. iliotibialis lateralis from Kumamoto Cochin crossbred roaster and broiler chickens.

1. Histochemical properties of M. iliotibialis lateralis were compared between Kumamoto Cochin (a Japanese native breed) crossbred roasters (KC roasters, 112 d of age) and normal broilers (56 d of age). 2. Myofibres were divided into Types II-R, II-I and II-W showing high, moderate and low reduced nicotinamide adenine dinucleotide dehydrogenase (NADH-DH) activities, respectively. 3. Subsarcolemmal formazan granules indicating very strong NADH-DH activity in Type II-R fibres were observed only in KC roasters. In both sexes the percentage of Type II-R fibres present was greater in KC roasters than in broilers. 4. These results indicated marked differences in histochemical properties and meat quality between KC roasters and broilers.

Animals↗