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Neuropeptide Y (NPY)-related peptides in the common dogfish (Scyliorhinus canicula): Distribution and cardiovascular effects
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NEUROPEPTIDE Y (NPY)-RELATED PEPTIDES IN THE COMMON DOGFISH (SCYLIORHINUS CANICULA): DISTRIBUTION AND CARDIOVASCULAR EFFECTS. C. BJENNING ~, N. HAZON 2, S. HOLMGREN 1 and J.M. CONLON a. Zoophysiology, University of G6teborg, Box 250 59, S-400 31 G6teborg, Marine Laboratory, University of St Andrews, KY16 8LB, Scotland and Biomedical Sciences, Creighton University School of Medicine, Omaha, NE
1Department of Sweden; :Gatty aDepartment of 68178, USA.
NPY has been isolated and sequenced from the brain and the pancreas of the dogrish (1, 2). The primary structures have been determined and confirmed by chemical synthesis. Both pancreatic and brain NPY peptides show strong structural similarity to porcine NPY, particularly in the COOH-terminai region. Immunohistochemistry revealed that NPY-like immunoreactivity is present in nerve fibers and endocrine cells in Scyliorhinus. The nerve fibres were varicose, and present in high densities in the coeliac artery and the afferent gill artery, around submucosai vessels and between the muscle layers of the gut. The endocrine cells were found in the gut mucosa, predominantly in the posterior part of the spiral intestine. In vitro studies using a small vessel myograph revealed that pancreatic dogfish NPY elicited powerful concentration-dependent contractions in the dogfish afferent gill artery; the pD2 value (7.56 + 0.38, SD) was not altered by removal of the endothelium (7.1 + 0.56, SD) (N=5). We conclude that NPY-related peptides are present in the brain and alimentary tract of the common dogfish and are powerful vasoconstrictors of the dogfish gill vasculature. Conlon JM, A Balasubramaniamand N Hazon. Endocrinology 1991 (128:5) 2273-2279. Conlon JM, C Bjenning and N Hazon. Peptides 1992 (13) in press.
CHANGES IN ANTERIOR PITUITARY HORMONE CONTENT IN RATS TREATED NEONATALLY WITH ANTIBODIES TO RAT GROWTH HORMONE AND BOVINE GROWTH HORMONE. K. AKINSANYA, D. WYNICK, M.J. GARDNER', D.J. FLINT" & S.R.BLOOM. Royal Postgraduate Medical School, Du Cane Rd, London & 'Hannah Research Institute, Ayr KA6 5HL, Scotland.
A new model of dwarfism has been developed using a specific antiserum against rat GH to treat neonatal rats. Previous data has shown that treatment for up to 8 weeks with the antiserum causes a reduction in body weight gain, muscle and organ weights, bone lengths and various other parameters associated with endocrine function and growth. Treatment with bovine GH (bGH) normalised these changes. In addition, cultured anterior pituitary cells from animals treated with the antiserum show significantly reduced basal and stimulated release of growth hormone (GH), prolactin (PRL) and luteinizing hormone (LH). In this study animals were divided into six groups. One set were treated with sheep anti-rGH y globulin for B weeks (longterm) and half of these received bGH at the same time as the antiserum. A control group were treated with normal sheep y globulin also for a period of 8 weeks. A second set received similar treatments but for 4 weeks (short-term). The effect of these treatments on pituitary content of prolactin (PRL), growth hormone, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and thyroid stimulating hormone (TSH) were determined. Whole pituitaries were collected and frozen until extracted by homogenisation in a ] M Urea-phosphate buffered saline solution. Pituitary hormone content was then determined by radioimmunoassay employing NIDDK immuno-reagents. Both PRL and GH content were dramatically reduced in the antiserum treated group and were virtually returned to normal by bGH treatment. LH, FSH and TSH were unaffected. These results indicate that the antiserum is having a specific effect on the mammosommatotroph and suggests that the changes previously seen in LH release may be due to paracrine interactions. GH (pg/pituitary) PRL (Hg/pituitary) TSH (lJg/pituitary) LH (LIg/pituitary) FSH (pg/pituitary) Longterm control 16.6 -+ 1.5 22.0 ± ].] 2.9 +_0.27 0.47 _+0.06 4.0 _+0.32 Long-te~m + anti~GH 4.9 +- 0.51 " ' " ].7 *_0.38 "*" 1.9 +0.23 0.55 ± 0.04 3.8 = 0.23 Long-term+anti rGH+bGH 10.9 -+ 2.8 19.2 _+ 3.0 3.3 + 0.24 0.80 +- 0.06 3.1 ± 0.20 Short term control 16.5 ±.0.80 ]8.6 + 5.1 2.7 z0.21 0.45 _+0.05 3.9 -+ 0.35 Shortterm + anti rGH 7.5 _*0.23 " "" 5.8 +] .1 "'" 2.4 + 0.72 0.36 ± 0.08 5.0 ± 0.23 Shortterm+anti.rGH*bGH 17.6 -+ 1.6 125 ± 2.1 3.4 + 0.50 0.46 ± 0.04 4.0 ± 0.39 p <0001 = " "
NEUROPEPTIDE Y (NPY)-RELATED PEPTIDES IN THE COMMON DOGFISH (SCYLIORHINUS CANICULA): DISTRIBUTION AND CARDIOVASCULAR EFFECTS. C. BJENNING ~, N. HAZON 2, S. HOLMGREN 1 and J.M. CONLON a. Zoophysiology, University of G6teborg, Box 250 59, S-400 31 G6teborg, Marine Laboratory, University of St Andrews, KY16 8LB, Scotland and Biomedical Sciences, Creighton University School of Medicine, Omaha, NE
1Department of Sweden; :Gatty aDepartment of 68178, USA.
NPY has been isolated and sequenced from the brain and the pancreas of the dogrish (1, 2). The primary structures have been determined and confirmed by chemical synthesis. Both pancreatic and brain NPY peptides show strong structural similarity to porcine NPY, particularly in the COOH-terminai region. Immunohistochemistry revealed that NPY-like immunoreactivity is present in nerve fibers and endocrine cells in Scyliorhinus. The nerve fibres were varicose, and present in high densities in the coeliac artery and the afferent gill artery, around submucosai vessels and between the muscle layers of the gut. The endocrine cells were found in the gut mucosa, predominantly in the posterior part of the spiral intestine. In vitro studies using a small vessel myograph revealed that pancreatic dogfish NPY elicited powerful concentration-dependent contractions in the dogfish afferent gill artery; the pD2 value (7.56 + 0.38, SD) was not altered by removal of the endothelium (7.1 + 0.56, SD) (N=5). We conclude that NPY-related peptides are present in the brain and alimentary tract of the common dogfish and are powerful vasoconstrictors of the dogfish gill vasculature. Conlon JM, A Balasubramaniamand N Hazon. Endocrinology 1991 (128:5) 2273-2279. Conlon JM, C Bjenning and N Hazon. Peptides 1992 (13) in press.
CHANGES IN ANTERIOR PITUITARY HORMONE CONTENT IN RATS TREATED NEONATALLY WITH ANTIBODIES TO RAT GROWTH HORMONE AND BOVINE GROWTH HORMONE. K. AKINSANYA, D. WYNICK, M.J. GARDNER', D.J. FLINT" & S.R.BLOOM. Royal Postgraduate Medical School, Du Cane Rd, London & 'Hannah Research Institute, Ayr KA6 5HL, Scotland.
A new model of dwarfism has been developed using a specific antiserum against rat GH to treat neonatal rats. Previous data has shown that treatment for up to 8 weeks with the antiserum causes a reduction in body weight gain, muscle and organ weights, bone lengths and various other parameters associated with endocrine function and growth. Treatment with bovine GH (bGH) normalised these changes. In addition, cultured anterior pituitary cells from animals treated with the antiserum show significantly reduced basal and stimulated release of growth hormone (GH), prolactin (PRL) and luteinizing hormone (LH). In this study animals were divided into six groups. One set were treated with sheep anti-rGH y globulin for B weeks (longterm) and half of these received bGH at the same time as the antiserum. A control group were treated with normal sheep y globulin also for a period of 8 weeks. A second set received similar treatments but for 4 weeks (short-term). The effect of these treatments on pituitary content of prolactin (PRL), growth hormone, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and thyroid stimulating hormone (TSH) were determined. Whole pituitaries were collected and frozen until extracted by homogenisation in a ] M Urea-phosphate buffered saline solution. Pituitary hormone content was then determined by radioimmunoassay employing NIDDK immuno-reagents. Both PRL and GH content were dramatically reduced in the antiserum treated group and were virtually returned to normal by bGH treatment. LH, FSH and TSH were unaffected. These results indicate that the antiserum is having a specific effect on the mammosommatotroph and suggests that the changes previously seen in LH release may be due to paracrine interactions. GH (pg/pituitary) PRL (Hg/pituitary) TSH (lJg/pituitary) LH (LIg/pituitary) FSH (pg/pituitary) Longterm control 16.6 -+ 1.5 22.0 ± ].] 2.9 +_0.27 0.47 _+0.06 4.0 _+0.32 Long-te~m + anti~GH 4.9 +- 0.51 " ' " ].7 *_0.38 "*" 1.9 +0.23 0.55 ± 0.04 3.8 = 0.23 Long-term+anti rGH+bGH 10.9 -+ 2.8 19.2 _+ 3.0 3.3 + 0.24 0.80 +- 0.06 3.1 ± 0.20 Short term control 16.5 ±.0.80 ]8.6 + 5.1 2.7 z0.21 0.45 _+0.05 3.9 -+ 0.35 Shortterm + anti rGH 7.5 _*0.23 " "" 5.8 +] .1 "'" 2.4 + 0.72 0.36 ± 0.08 5.0 ± 0.23 Shortterm+anti.rGH*bGH 17.6 -+ 1.6 125 ± 2.1 3.4 + 0.50 0.46 ± 0.04 4.0 ± 0.39 p <0001 = " "