Autoradiographic visualization of the binding sites for [125I]endothelin in rat and human brain

Jones, C. R.; Pelton, John T.; Mohr, Michel

doi:10.1016/0304-3940(89)90610-1

Cited by 233 publications

(79 citation statements)

References 7 publications

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“…Future studies should be aimed at determining whether the apparent receptor subtypes described here are associated with different second messenger systems. It has already been shown that one of them, which binds ET-1 and SRTX-b with high affinity [1,2,14,15] and appears to correspond to the E-S,, subtype, is associated with phosphoinositide hydrolysis [1,3,4] and Ca 2+ mobilization [16,17]. It would also be of interest to identify the endogenous agonist for the E-Sa receptors, for which SRTX-c appears to be a selective agonist, and to determine whether or not there exists a selective natural agonist for E-St receptor.…”

Section: Discussionmentioning

confidence: 99%

Three apparent receptor subtypes for the endothelin/sarafotoxin family

et al. 1989

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Competition binding experiments performed with 125 I-sarafotoxin (SRTX)-b and SRTX-b, SRTX-c and endothelin (ET-1 and ET-3) using homogenates of rat right and left atria, aorta, uterus, cerebellum and candate putamen indicated heterogeneity of the ET/SRTX receptor. The evidence pointed to the existence of three receptor subtypes: a high-atfmity ET-1/ SRTX-b subtype typical of smooth muscle (E-S~ receptor), a high-affinity SRTX-c subtype typical of the cerebellum (E-S# receptor), and a less selective subtype typical of the caudate putamen that binds all of these peptides with high affinity (E-S r receptor).

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Section: Discussionmentioning

confidence: 99%

Three apparent receptor subtypes for the endothelin/sarafotoxin family

et al. 1989

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“…Further, endothelin-I was shown to be lovsky, 1989;Arai et al, 1990;Sakurai et al, 1990). These a modulator of neuronal activity (Yanagisawa & Masaki, receptors are distributed in peripheral tissues (Power et al, 1989), inducing a potent facilitation of the nerve-mediated 1989) and the central nervous system (Jones et al, 1989). twitch response at the post-junctional level on the rat vas Endothelin-I is one the most potent vasopressors known deferens (Maggi et al, 1989; Telemaque & D'Orleans-Juste, (Yanagisawa et al, 1988) and it is now widely accepted that 1991; Hiley et al, 1989) and inhibiting the twitch response in endothelin-I exerts its activities not only as a potent constricthe guinea-pig vas deferens (Wiklund et al, 1990) by a pre-junctional mechanism; these observations underline the possible role of the endothelins as neuromodulator peptides.…”

Section: Introductionmentioning

confidence: 99%

Comparison of the cardiovascular and neural activity of endothelin‐1, −2, −3 and respective proendothelins: effects of phosphoramidon and thiorphan

Mattera¹,

Eglezos²,

Renzetti³

et al. 1993

British J Pharmacology

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1 In the anaesthetized, ganglion-blocked rat, intravenous boluses of endothelin-1, endothelin-2 and endothelin-3 induced a transient hypotensive effect followed by a potent long lasting pressor response (ED_sommHg: 0.72 ± 0.05, 1.8 ± 0.2 and 2.7 ± 0.3 nmol kg-', respectively). The maximal effect for the three peptides was of a similar order of magnitude (,&MAP: 84 to 89 mmHg). Neither of these effects was influenced by phosphoramidon or thiorphan (10 mg kg-', i.v.).2 Intravenously administered big-endothelin-1 and -2 induced a transient (1-2 min) hypotension followed by a potent long lasting (>25 min) vasopressor effect (ED50,.Hg: 1.8 ± 0.2 and 6.7 ± 0.4 nmol kg-', respectively), with a similar maximal activity (A MAP: 85 ± 4 and 81 ± 2.4 mmHg, respectively). The onset of the big-endothelin-l vasopressor effect was more rapid (5-6 min) than that of big-endothelin-2 (10-13 min). Big-endothelin-3 was found to induce only a potent, long lasting (>35 min) hypertension, with a maximal effect of 75 ± 4.6 mmHg at 10 nmol kg-' and an ED50,,,,Hg of 6.5 ± 0.4 nmol kg-'. The onset of this effect was much slower (20-25 min) than that of the other proendothelins. Pressor responses induced by big-endothelin-1, -2 and -3 (3, 15 and 10 nmol kg-', respectively) were markedly reduced (60, 80 and 100%) in the presence of phosphoramidon (10 mg kg-', i.v.). Thiorphan (10 mg kg', i.v.) did not inhibit the effects of big-endothelin-1, -2 and -3. 3 In the electrically stimulated rat vas deferens, endothelin-I and -2 were found to be equipotent enhancers of the twitch response (EC,00%: 4.0 ± 0.4 nm and 7.9 ± 4.8 nm, respectively), both about 3-4 fold as active as endothelin-3 (EC,00%: 19 ± 2.5 nM). Endothelin-1 and -3 showed a comparable maximal stimulatory effect (Emax: 296 ± 30 and 262 ± 24%) while endothelin-2 was less active (Em,,: 194 ± 30%).4 Big-endothelin-l and -2 were potent enhancers of the twitch reponse too (EC 1o,%: 10.0 ± 2.6 nM and 21.6 + 3.2 nM, respectively), with a comparable maximal stimulatory effect (Ema: 254 ± 22 and 264 ± 24%). Big-endothelin-3 was found to be less potent (EC,0o%: 275 ± 21 nM), but retained a marked potentiating effect (Emax: 200 ± 38%). Phosphoramidon, but not thiorphan, concentration-dependently (10 and 100 JM) reduced big-endothelin-1 (58 and 86% respectively) and big-endothelin-2 (21 and 56%) -mediated responses. Conversely, the big-endothelin-3 effect was reduced by phosphoramidon only at 100#JM (-70%), while thiorphan acts concentration-dependently (31 and 71% at 10 and 100JIM respectively); thus, in the rat vas deferens, big-endothelin-I and -2 were as potent as their corresponding endothelins, while big-endothelin-3 was about 20 times less potent than endothelin-3. 5 The increasing effect of endothelin-2 (194 ± 30% over baseline) was significantly enhanced by either 10 JIM phosphoramidon (277 ± 42%) or thiorphan (318 ± 15%). The endothelin-I and endothelin-3-mediated twitch enhancement was not affected by the two protease inhibitors (10JIM). 6 These results suggest that in vivo big-endoth...

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“…ET mRNA [3][4][5][6], and binding sites or receptors for ET [3,[6][7][8] have been found to be distributed widely in mammals, including in the brain. Furthermore, the similarity of localization of both mRNA and receptors for ET suggests that ET may act as a local factor [3,5,6].…”

Section: Endothelinsmentioning

confidence: 99%

Immunoreactive Endothelin-1 in the Neural Lobe of the Rat Pituitary following Hemorrhage and Dehydration.

Uemura

Naruse²,

Nakamura

et al. 1994

Endocr J

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Abstract. Previously we found intragranular colocalization of immunoreactive endothelin-1 and neurohypophysial hormones in the axon terminals of the rat neural lobe. To investigate the function of endothelin-1 in the rat neural lobe, immunoreactive endothelin-1 in plasma and the neural lobe was measured by enzyme immunoassay in rats subjected to hemorrhage and in other rats who were deprived of water for 2 days to induce dehydration. Changes in plasma arginine vasopressin were determined by radioimmunoassay.In addition, morphometric analysis was performed in the neural lobe of rats exposed to these stresses. Plasma concentrations of immunoreactive endothelin-1 were unchanged following hemorrhage or dehydration, whereas those of immunoreactive vasopressin were remarkably increased. In the neural lobe, immunoreactive endothelin-1 content and the number of neurosecretory granules decreased significantly after dehydration.However, immunoreactive endothelin-1 in tissue increased nearly three-fold in hemorrhaged rats, whereas the endothelin-1-immunolabeling in the axon terminals was unchanged. These results suggest that endothelin-1 in the hypothalamo-hypophysial system may be involved in the local modulation of vasopressin secretion when an animal is exposed to hypovolemic and/or osmotic stress.

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Autoradiographic visualization of the binding sites for [125I]endothelin in rat and human brain

Cited by 233 publications

References 7 publications

Three apparent receptor subtypes for the endothelin/sarafotoxin family

Three apparent receptor subtypes for the endothelin/sarafotoxin family

Comparison of the cardiovascular and neural activity of endothelin‐1, −2, −3 and respective proendothelins: effects of phosphoramidon and thiorphan

Immunoreactive Endothelin-1 in the Neural Lobe of the Rat Pituitary following Hemorrhage and Dehydration.

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