Effect of adrenergic blockade on the pheromonal restoration of cyclic activity in young oestrogen-primed persistent oestrous female rats.
The effects of adrenergic blockade on pheromonal restoration of cyclic activity were studied in acute oestrogenized persistent oestrous young female rats. Hypothalamic luteinizing hormone-releasing hormone (LHRH) and plasma LH, follicle-stimulating hormone (FSH), oestradiol and progesterone were measured by specific radio-immunoassays, and prolactin by enzyme-linked immunosorbent assay in: (i) young cycling rats; (ii) young persistent oestrous female rats; (iii) young persistent oestrous females treated with nasal sprays of male urine; and (iv) young persistent oestrous females treated with nasal sprays of male urine and injected with saline, propranolol, prazosin or yohimbine. LHRH was low 24 h after oestradiol benzoate injection, increasing up to 15 days later; LH, FSH, oestradiol and progesterone ranged from high values 24 h after oestradiol benzoate injection to low 15 days later; prolactin ranged from low concentration 24 h after oestradiol benzoate injection to high 15 days later. Male urine treatment induced a depletion of LHRH, a rise of LH, FSH and progesterone, pheromonal restoration of cyclic activity and a normal hormonal cyclic pattern. Treatment with prazosin and yohimbine prevented the pheromonal restoration of cyclic activity, the drop of LHRH and the rise of plasma concentration of the studied hormones induced by male urine, while saline or propranolol did not. These results show the hormonal pattern of the pheromonal restoration of cyclic activity in persistent oestrous rats and strongly suggest that alpha-adrenergic inputs to the hypothalamus may be involved in this pheromonal effect.
Mora
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A
Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Spain. morano@med.ucm.es
Sánchez-Criado
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JE
D000281:Administration, Intranasal; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D004958:Estradiol / Q000494:pharmacology*; D004971:Estrus / Q000187:drug effects*; D005260:Female; D006728:Hormones / Q000097:blood; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects; D008297:Male; D010053:Ovary / Q000187:drug effects; D010675:Pheromones / Q000502:physiology*; D011224:Prazosin / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012727:Sex Characteristics; D014556:Urine / Q000502:physiology; D015016:Yohimbine / Q000494:pharmacology
D000317:Adrenergic alpha-Antagonists; D006728:Hormones; D010675:Pheromones; D015016:Yohimbine; D004958:Estradiol; D011224:Prazosin