[Role of adrenoreceptors in the effect of thyroliberin on lymphatic vessels].
Formerly we showed that TRH had simulative effect on mesenteric bovine and rat lymphatic vessels (LV) in very low concentration--10(-12)-10(-18) M. In present paper, participation of LV alpha- and beta-receptors in realization of TRH activity on rat mesenteric lymphatic vessels was studied in situ. Propranolol increased the stimulative effect of TRH, isoproterenol exerted an opposite effect. Phentolamine, prazosin eliminated the simulative effect of TRH, yohimbine resulted in additional gain of effect, which seems to testify 1) presynaptic action of TRH or 2) increase of the output of norepinephrine, which is potentiated by alpha 2-adrenoceptor antagonists. Also the participation of adrenergic receptors in positive chronotropic effects of mesenteric rat LV was studied using the method of selective destruction of dopamine-containing neurons after 6-OHDA infusion. As it occurred, desympathization hindered development of stimulating action of TRH. Thus, the efficiency of TRH as a stimulator of LV is connected with activation of adrenergic mechanisms.
Lelekova
T V
TV
Lomonossov State University, 119899, Moscow, Vorobievy Gory, Russia.
Sanzhieva
L Ts
LTs
D000322:Adrenergic Agonists / Q000494:pharmacology; D018674:Adrenergic Antagonists / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D066298:In Vitro Techniques; D042601:Lymphatic Vessels / Q000502:physiology*; D008297:Male; D008643:Mesentery; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D011941:Receptors, Adrenergic / Q000187:drug effects / Q000502:physiology*; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology / Q000502:physiology*
D000322:Adrenergic Agonists; D018674:Adrenergic Antagonists; D011941:Receptors, Adrenergic; D013973:Thyrotropin-Releasing Hormone