It is still unclear whether, in the male rat, castration and androgen replacement affect the binding characteristics of brain opiate receptors. To clarify this issue, the effects exerted by orchidectomy and testosterone (T) replacement on the subpopulation of brain mu opiate receptors were studied in male rats; testosterone was administered via subcutaneous Silastic capsules. Utilizing 3H-dihydromorphine (a mu receptor ligand) it has been shown that the affinity constant (Ka) of brain mu opiate binding sites, measured in plasma membrane preparations, is not affected by castration. When mu receptor concentrations were measured in individual brains, it was found that gonadectomy and T replacement failed to produce any change in the number of mu opiate receptors. These data suggest that, in male rats, gonadal steroids do not develop their central feedback effects by affecting brain mu opiate receptors.

Further evidence that gonadal steroids do not modulate brain opiate receptors in male rats / M. Olasmaa, P. Limonta, R. Maggi, D. Dondi, L. Martini, F. Piva. - In: ENDOCRINOLOGIA JAPONICA. - ISSN 0013-7219. - 34:4(1987 Aug), pp. 521-529. [10.1507/endocrj1954.34.521]

Further evidence that gonadal steroids do not modulate brain opiate receptors in male rats

P. Limonta
Secondo
;
R. Maggi;D. Dondi;L. Martini
Penultimo
;
F. Piva
Ultimo
1987

Abstract

It is still unclear whether, in the male rat, castration and androgen replacement affect the binding characteristics of brain opiate receptors. To clarify this issue, the effects exerted by orchidectomy and testosterone (T) replacement on the subpopulation of brain mu opiate receptors were studied in male rats; testosterone was administered via subcutaneous Silastic capsules. Utilizing 3H-dihydromorphine (a mu receptor ligand) it has been shown that the affinity constant (Ka) of brain mu opiate binding sites, measured in plasma membrane preparations, is not affected by castration. When mu receptor concentrations were measured in individual brains, it was found that gonadectomy and T replacement failed to produce any change in the number of mu opiate receptors. These data suggest that, in male rats, gonadal steroids do not develop their central feedback effects by affecting brain mu opiate receptors.
Rats, Inbred Strains; Rats; Morphine Derivatives; Animals; Testosterone; Luteinizing Hormone; Receptors, Opioid, mu; Receptors, Opioid; Brain; Dihydromorphine; Male; Orchiectomy
Settore BIO/13 - Biologia Applicata
ago-1987
Article (author)
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/181859
Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus 12
  • ???jsp.display-item.citation.isi??? ND
social impact