Elevated neuropeptide Y concentrations in the central hypothalamus of the spontaneously diabetic BB/E Wistar rat.
Insulin-deficient diabetes causes hypothalamic and pituitary dysfunction. The possible role of hypothalamic regulatory peptides in mediating these disturbances was investigated in spontaneously diabetic BB/E Wistar rats. Concentrations of 10 regulatory peptides were measured in the central (nucleus-rich) and lateral parts of the hypothalamus in 18 diabetic and 5 non-diabetic BB/E rats. Diabetic rats were treated with either intensified or low-dose insulin schedules to achieve moderate or severe hyperglycaemia (mean blood glucose concentrations, 8 and 20 mmol l-1 respectively). Neuropeptide Y concentration and content in the central hypothalamus were increased by 30-40% in both moderately and severely hyperglycaemic diabetic groups (p less than 0.01). Lateral hypothalamic neuropeptide Y levels did not differ significantly between the groups. The only other peptide to show any significant difference between diabetic and control rats was calcitonin gene-related peptide, whose central hypothalamic concentrations were significantly increased in the severely hyperglycaemic animals. Alterations of hypothalamic neuropeptide Y, which has potent experimental effects on hypothalamo-pituitary function, may contribute to certain neuroendocrine disturbances in insulin-deficient diabetes.
Williams
G
G
Francis Fraser Laboratories, Department of Medicine, Royal Postgraduate Medical School, London, UK.
Lee
Y C
YC
Ghatei
M A
MA
Cardoso
H M
HM
Ball
J A
JA
Bone
A J
AJ
Baird
J D
JD
Bloom
S R
SR
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D013006:Growth Hormone / Q000097:blood; D007031:Hypothalamus / Q000032:analysis*; D007328:Insulin / Q000097:blood; D008297:Male; D009478:Neuropeptide Y / Q000032:analysis*; D009479:Neuropeptides / Q000032:analysis*; D011863:Radioimmunoassay; D051381:Rats; D011913:Rats, Inbred BB / Q000378:metabolism*; D011919:Rats, Inbred Strains / Q000378:metabolism*; D012016:Reference Values
D001786:Blood Glucose; D007328:Insulin; D009478:Neuropeptide Y; D009479:Neuropeptides; D013006:Growth Hormone