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Biomedical subjects

C W Xie

Publications and source records attributed to C W Xie.

At least 37 records · Page 2Linked to original sources
PubMed1989

[Dynorphin and atriopeptin may be involved in the depressor mechanism of clonidine].

Intravenous injection (iv) of clonidine significantly induced depressor and bradycardiac responses in rats. These responses were found to be blocked by iv alpha-adrenoreceptor blocker phentolamine, intraperitoneous injection (ip) of naloxone (10mg/kg) or iv antidynorphin-IgG(80 microliters). Furthermore, clonidine (iv) induced a significant increase of urine volume, which was also partly blocked by naloxone (10mg/kg). A dramatic increase of rat plasma immunoreactive atriopeptin induced by clonidine (iv) was partly antagonised by pretreatment with naloxone (4mg/kg) or phentolamine (10mg/kg). These results show that dynorphin and atriopeptin may be involved in the depressor mechanism of clonidine.

Animals↗
PubMed1988

A dynorphin peptide induces hypotension by stimulating the release of atrial natriuretic peptide from rat atrium.

Intravenous injection of dynorphin A-(1-10) amide (Dyn, 81-324 nmol/kg) induced a dose-dependent hypotensive effect in the rat. This effect was antagonized by pretreatment with immunoglobulin G, purified from a specific antiserum raised against alpha-human atrial natriuretic peptide (anti-hANP-IgG), as well as by high doses of naloxone (2 or 10 mg/kg). In addition, a 12-fold increase in plasma level of atrial natriuretic peptide-like immunoreactivity (ANP-IR) was found following Dyn administration, which was accompanied by a significant decrease of atrial ANP-IR. These results suggest that the stimulated release of ANP-IR from the atrium may constitute one of the mechanisms for the depressor effect of dynorphin peptides.

Animals↗
PubMed1988

[Alpha-hANP-like immunoreactivity in lung cancer].

Specific radioimmunoassay and immunohistochemical method of alpha-human atrial natriuretic polypeptide (alpha-hANP) was established to diagnose one case of large cell lung carcinoma (clear cell carcinoma) proved by pathology. It was found that there was alpha-hANP-like immunoreactivity in the cancer cells at a concentration of 147.5 pg/mg protein. Chromatography analysis showed that alpha-hANP-like immunoreactive materials had multiple molecular forms. The significance of these phenomena remains to be further investigated.

Adenocarcinoma↗
PubMed1987

Therapeutic actions of alpha-human atrial natriuretic polypeptide in 16 clinical cases.

Alpha-human atrial natriuretic polypeptide (alpha-hANP) was applied to 16 clinical patients, 6 patients with essential hypertension, 7 patients with congestive heart failure and 3 patients with cirrhosis. Following intravenous bolus injection of 400 micrograms of synthetic alpha-hANP, a hypotensive effect of very rapid onset was found, which was more potent in the hypertensive patients than in the normotensive cases. Cardiac functions were improved significantly with a similar time course as the depressor response in the cases of heart failure or hypertension. Hemodynamic observations showed a marked increase in cardiac output, cardiac index, stroke volume, ejection fraction and ejection rate, and a concomitant decrease of the pressure in the right side of the heart and pulmonary circulation in these subjects. In addition, the renal response to alpha-hANP induced obvious increases in urine volume, electrolytes and creatinine excretions in all the subjects. Finally, plasma levels of aldosterone, Arg-vasopressin and noradrenaline were also altered by alpha-hANP. No significant side effects were registered. The above result confirms the therapeutic actions of alpha-hANP in human subjects and opens the possibility to research alpha-hANP as a powerful pharmacological tool as well as potential new medicine for human disorders.

Adult↗
PubMed1986

Clonidine stimulated the release of dynorphin in the spinal cord of the rat: a possible mechanism for its depressor effects.

The decrease in blood pressure, heart rate and sympathetic nervous discharges (SND) induced by intrathecal injection of clonidine (1 microgram) in the rat was prevented by pretreatment with intrathecal injection of an antiserum against dynorphin. Clonidine (10(-4) M) added to the artificial cerebrospinal fluid perfusing the spinal subarachnoid space of the rat increased the amount of immunoreactive dynorphin in the perfusate. Intrathecal injection of dynorphin (30 micrograms) caused hypotension, bradycardia and a reduction in SND. These results suggest that the release of dynorphin in the spinal cord may constitute one of the mechanisms for the depressor effects of clonidine.

Animals↗
PubMed1986

Atriopeptin and spontaneous hypertension in rats.

The involvement of atriopeptin in hypertension was investigated in spontaneously hypertensive rats (SHR). It was found that intravenous injection of atriopeptin III (20-80 nmol/kg) markedly decreased the mean arterial pressure in anesthetized SHR in a dose dependent manner. The heart rate was not significantly affected. The contents of atriopeptin immunoreactive material in the rat atrium and plasma were measured with radioimmunoassay. Both the atrium and plasma contents of atriopeptin immunoreactive material were found to be significantly higher in SHR than in the normotensive control Wistar Kyoto (WKY), indicating an increase in the biosynthesis and release of atriopeptin in SHR. Whether this change was a compensatory response induced by hypertension remains to be investigated.

Animals↗