Centrally infused galanin-(1–15) but not galanin-(1–29) reduces the baroreceptor reflex sensitivity in the rat
| Autor: | Zaida Diaz, Kjell Fuxe, J.A. Narváez, J.A. Aguirre, Salvador González-Barón, Peter B. Hedlund |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Male
endocrine system medicine.medical_specialty Baroreceptor Central nervous system Neuropeptide Blood Pressure Galanin Pressoreceptors Galanin receptor Rats Sprague-Dawley Phenylephrine Heart Rate Internal medicine medicine Animals Molecular Biology Injections Intraventricular Chemistry General Neuroscience Neuropeptides digestive oral and skin physiology Hemodynamics Baroreflex Effective dose (pharmacology) Peptide Fragments Rats medicine.anatomical_structure Endocrinology nervous system Reflex bradycardia Neurology (clinical) Adrenergic alpha-Agonists hormones hormone substitutes and hormone antagonists Developmental Biology medicine.drug |
| Zdroj: | Brain Research. 741:32-37 |
| ISSN: | 0006-8993 |
| DOI: | 10.1016/s0006-8993(96)00883-9 |
| Popis: | It has been demonstrated previously that central administration of the N-terminal galanin fragment (1–15) elicits hypertension and tachycardia and antagonizes the hypotensive effect of the parent molecule galanin-(1–29). In order to further clarify the role of galanin in central cardiovascular control, the possible modulation of the baroreceptor reflex by both galanin molecules has been studied. Different groups of rats were injected in the lateral ventricle with subthreshold doses of galanin-(1–15) (0.1 nmol/rat, or 0.3 nmol/rat), with subthreshold doses of galanin-(1–29) (0.1 nmol/rat, and 0.3 nmol/rat) or with an effective dose of galanin-(1–29) (3.0 nmol/rat). The baroreceptor reflex was elicited by intravenous injections of different doses of l -phenylephrine before and after the intraventricular administration of galanin peptides. The changes of the bradycardic responses after galanin peptide injections as well as the modifications of the baroreceptor reflex sensitivity were evaluated. Intraventricular injections of galanin-(1–15) significantly inhibited the reflex bradycardia elicited by intravenous l -phenylephrine and thus decreased the baroreceptor sensitivity. However, neither subthreshold doses of galanin-(1–29) nor its effective dose were able to modulate these cardiovascular responses. From these data it may be suggested that the galanin fragment (1–15) plays a more important role in central cardiovascular regulation than galanin-(1–29), possibly acting on a specific receptor subtype which exclusively recognizes N-terminal fragments of galanin, and exists on cardiovascular areas of the central nervous system. |
| Databáze: | OpenAIRE |
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