Autoradiographic localization of binding sites for [3H]histamine and H1- and H2-antagonists on cultured neurones and glial cells.
By means of autoradiography we have studied the cellular localization of binding of [3H]histamine and H1- and H2-antagonists in explant cultures of rat cerebellum, brain stem and spinal cord. In brain stem and spinal cord cultures, a relatively great number of neurones revealed binding sites for [3H]histamine and to a lesser extent also for the H1-antagonist [3H]pyrilamine and for the H2-antagonist [3H]tiotidine. In contrast, only a small number of labelled neurones was found in cerebellar cultures. The intensity of labelling was usually much stronger for [3H]histamine than for its antagonists, suggesting that binding sites for histamine might reflect both H1- and H2-receptors. Glial cells also showed binding sites for [3H]histamine and the H1- and H2-antagonists, the number of labelled astrocytes by these radioligands was, however, smaller than that observed with [3H]noradrenaline and alpha- and beta-adrenergic antagonists. It is suggested that in addition to alpha- and beta-adrenoceptors, glial cells also possess receptors for histamine.
D000818:Animals; D001933:Brain Stem / Q000378:metabolism; D002490:Central Nervous System / Q000378:metabolism*; D002531:Cerebellum / Q000378:metabolism; D046508:Culture Techniques; D006632:Histamine / Q000378:metabolism*; D009457:Neuroglia / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D051381:Rats; D011968:Receptors, Histamine / Q000378:metabolism*; D011969:Receptors, Histamine H1 / Q000378:metabolism*; D011970:Receptors, Histamine H2 / Q000378:metabolism*; D013116:Spinal Cord / Q000378:metabolism
D011968:Receptors, Histamine; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D006632:Histamine