Serum insulin, glucose and non esterified fatty acids after administration of follicle-stimulating and luteinizing hormones in bitches

Abstract

This paper reports the effect of the simultaneous administration of follicle-stimulating (FSH) and luteinizing hormones (LH) on serum glucose, insulin and nonesterified fatty acid responses after glucose or insulin challenge. The animals were originally at anestrous. FSH (dose 2.5 U/kg body wt.) and LH (0.27 U/kg body wt.) were s.c. injected on days 1, 4, 8 and 11. Vaginal smears were obtained daily. Six untreated controls at anestrous and six treated bitches reaching proestrous were used. Glucose tolerance tests were done with a dose of 1 g of glucose per kg of body weight. Bovine insulin was administered at the dose of 0.25 U/kg body wt. During these tests, neither serum glucose and nonesterified fatty acids nor glucose distribution space and glucose clearance were affected by the treatment. The serum insulin response to hyperglycemia was greatly increased. The distribution space and clearance rate of this hormone were not affected by FSH + LH treatment. We conclude that, in the bitch, FSH + LH treatment, at doses that trigger "sex seasons", increases the serum insulin response to glucose load and produces a moderate resistance to the hypoglycemic, lipogenic and antilipolytic insulin actions. These phenomena are evident during hyperglycemia.