Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The centrally induced effects of angiotensin II and substance P on the cardiovascular system and on neuronal efferent activity of the splanchnic, renal, and adrenal nerves were investigated in chronically instrumented conscious rats. The pressor responses to substance P injected into the lateral brain ventricle were accompanied by marked and short latency increases in heart rate, cardiac output, splanchnic, renal, and adrenal nerve activity, and a rise in plasma noradrenaline and adrenaline. Behaviorally, an arousal-type reaction was observed. In contrast, the pressor responses to intracerebroventricular angiotensin II were associated with initial decreases in heart rate, cardiac output, splanchnic, renal, and adrenal nerve activity, and a fall in plasma noradrenaline at the time of the maximal blood pressure increase. In some but not all animals, a second blood pressure peak associated with increases in heart rate and splanchnic nerve activity was observed after several minutes. Incomplete chronic sinoaortic baroreceptor deafferentiation prevented the angiotensin II-induced fall in heart rate but not the initial fall in splanchnic nerve activity. The decreases in splanchnic nerve activity also occurred in diabetes insipidus rats and persisted in Long Evans rats after vascular vasopressin receptor blockade with d(CH2)5AVP, despite marked reductions of the pressor responses in both groups. Peripheral alpha-adrenoceptor blockade with prazosin or ganglion blockade with hexamethonium inhibited the central angiotensin II pressor responses only in combination with vasopressin receptor blockade. On the other hand, either sympatholytic drug, alone, abolished the pressor responses in the diabetes insipidus rats. This indicates that in intact conscious rats the central pressor effects of angiotensin II are initiated by vasopressin release but become dependent on the sympathetic nervous system when vasopressin is absent or not effective. When rats were allowed to drink in response to angiotensin II, a further sharp rise in blood pressure occurred, together with increases in heart rate and splanchnic nerve activity. The results demonstrate fundamental differences in the mechanisms by which central pressor peptides can influence cardiovascular and autonomic function. It is conceivable that the distinct sympathetic response patterns to central angiotensin II and substance P receptor stimulation form part of a specific cardiovascular adjustment to the individual behavioral reactions, such as drinking, as in the case of angiotensin II, or arousal within the central processing of pain, as in the case of substance P.
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PMID:Differential effects of central angiotensin II and substance P on sympathetic nerve activity in conscious rats. Implications for cardiovascular adaptation to behavioral responses. 257 49

Several neuroactive peptides have been implicated in thirst and sodium appetite in different species; three peptides are considered here. The best established of these is the octapeptide angiotensin II, which when administered systemically or intracranially causes completely normal drinking behaviour in all vertebrates tested, including many mammals, four or five birds, one reptile and one bony fish. In the rat, in which the original experiments were carried out, injection of a few femtomoles of angiotensin II caused a brisk drinking response within a minute or so of injection at a time of day when the animal would usually be resting. The response is usually completed within 10 min and after the larger doses the amounts of water taken may approach what the animal would normally drink in the course of 24 h. Another response to intracranial angiotensin, seen so far only in the rat, is an increase in sodium appetite. This is slower in onset than thirst, lasts for many hours and the response tends to become greater with repeated injections of hormone. Naturally occurring increases in sodium appetite may be caused by angiotensin generated by the action of cerebral isorenin. A second neuroactive peptide that affects thirst is the undecapeptide eledoisin, which is found in the salivary glands of certain Mediterranean cephalopods. Eledoisin and, to a lesser extent, substance P, with which it is related, are potent intracranial dipsogens in the pigeon, producing behaviour that is indistinguishable from that produced by angiotensin. However, in contrast to the stimulatory action of angiotensin on drinking behaviour in all other vertebrate species tested, these substances specifically depress drinking in the rat. A third peptide that has been implicated in thirst is antidiuretic hormone (ADH). This hormone has a profound but indirect effect on water intake in diabetes insipidus. In the dog, however, ADH in physiological amounts may influence thirst mechanisms by direct action on the central nervous system. In this species, but not in the rat, ADH lowers the threshold of thirst in response to osmotic stimulation and also to infusion of angiotensin. Of these three peptides, and others not mentioned here, angiotensin II has the best claim to be regarded as a neuroactive peptide. It alone is always dipsogenic when injected into the brain and it also stimulates sodium appetite. Whether the effects of angiotensin, on thirst and sodium appetite should be regarded as manifestations of the activity of a classical endocrine system, of a paracrine system, of a neurotransmitter system, or of all of these, cannot be decided at present. But these actions of angiotensin, when considered with its other actions on the distribution and conservation of body fluid, show that the hormone is intimately concerned in extracellular fluid volume control.
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PMID:Angiotensin and other peptides in the control of water and sodium intake. 615 52

The concentration of immunoreactive somatostatin and Substance P in the cisternal cerebrospinal fluid (CSF) of patients with pain due to malignant disease has been measured before and after injection of alcohol into the pituitary fossa. Following the first injection, a rise of 108 +/- 66% in CSF somatostatin levels was observed in 7 out of 13 patients, and a rise of 87 +/- 26% in 4 out of the 5 patients undergoing a second injection. A rise of 179 +/- 99% in levels of Substance P in CSF was observed in 4 out of 8 patients after a single injection. No change in peptide concentration was detected in peripheral plasma. Changes in CSF levels did not correlate with the degree of pain relief obtained, but patients with the greatest increase in somatostatin subsequently developed diabetes insipidus. The data are consistent with our previous experience that injection of alcohol into the pituitary fossa can cause destruction to nervous tissue, in addition to the obvious destruction of pituitary gland tissue. They do not support the suggestion that hypothalamic damage is necessary in order to obtain pain relief.
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PMID:Changes in the concentration of somatostatin and substance P in the cerebrospinal fluid following injection of alcohol into the pituitary gland. 620 18

A 44-year-old woman with Marie-Bamberger's syndrome and diabetes insipidus had a lung tumour with mediastinal metastases, but no signs of metastases to the hypothalamus or pituitary gland. A week after removal of the tumour, the joint pain, polyuria and polydipsia disappeared. The tumour was diagnosed histopathologically as a moderately differentiated adenocarcinoma with focal neuroendocrine cell differentiation and dispersed cells reacting with antisera against neurone-specific enolase, S-100 protein, neuropeptide Y, follicle-stimulating hormone, substance P, vasoactive polypeptide (VIP), adrenocorticotropic hormone and pancreatic polypeptide (PP) as well as to one of three tested antisera raised against antidiuretic hormone (ADH). It was suggested that Marie-Bamberger's syndrome might be caused by one of these immunoreactive substances or by a substance that shares an amino acid sequence with one of these neuroendocrine peptides. It was also suggested that the tumour might produce an ADH-like substance which might have an ADH-antagonist effect.
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PMID:Recovery from Marie-Bamberger's syndrome and diabetes insipidus after removal of a lung adenocarcinoma with neuroendocrine features. 956 47