Effect of sympathetic input on ontogeny of beta-adrenergic receptors in rat pineal gland.
The ontogeny of beta-adrenergic receptors was investigated in the pineal glands of rats 1-64 days of age. The density of beta-receptors increased about 3-fold between 1 and 16 days of age and decreased slightly by 64 days, correlating temporally with the development of the sensitivity of adenylate cyclase to norepinephrine in pineal gland. Preventing adrenergic innervation of the pineal gland by neonatal ganglionectomy or decentralization failed to prevent the development of beta-adrenergic receptors in pineal gland. Bilateral adrenal demedullation alone or in combination with ganglionectomy also failed to prevent the normal developmental increase of beta-receptors in the gland. These results, showing that the ontogeny of pineal beta-receptors correlated temporally with that of the responsiveness of adenylate cyclase to adrenergic neurohormones, support the hypothesis that the responsiveness of tissues ot beta-agonists is dependent on the development of the beta-receptor. In addition, these experiments show that the beta-adrenergic receptor can develop even in the absence of sympathetic innervation or circulating catecholamines produced by the adrenal medullae.
D000320:Adrenergic Fibers / Q000502:physiology*; D000375:Aging; D000818:Animals; D004082:Dihydroalprenolol / Q000378:metabolism; D005260:Female; D005728:Ganglia, Sympathetic / Q000502:physiology; D007700:Kinetics; D008297:Male; D010870:Pineal Gland / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D011941:Receptors, Adrenergic / Q000502:physiology*; D011943:Receptors, Adrenergic, beta / Q000502:physiology*
D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D004082:Dihydroalprenolol