Evidence for a role of N-methyl-D-aspartate receptors in L-arginine-induced attenuation of morphine antinociception.

Twice daily injections of L-arginine (50, 100 or 200 mg/kg, i.p.) for 4 days dose-dependently, decreased morphine antinociception in male Swiss-Webster mice as measured by the tail-flick test.

Role of ET and NO in resuscitative effect of diaspirin cross-linked hemoglobin after hemorrhage in rat.

Diaspirin cross-linked hemoglobin (DCLHb) is a hemoglobin-based therapeutic agent that produces significant cardiovascular effects, possibly due to its actions on vasoactive substances, such as endothelin (ET) and nitric oxide (NO). We have studied the modulation of cardiovascular effects of DCLHb by an NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), and an ETA-receptor antagonist, FR-139317, in hemorrhaged rats. Control rats resuscitated with vehicle [Ringer lactate (RL), 4 ml/kg iv] did not show any improvement in O2 consumption, base deficit, systemic hemodynamics, or regional blood flow after hemorrhage, and the rats survived for < 70 min.

Role of endothelin-converting enzyme in the systemic hemodynamics and regional circulatory effects of proendothelin-1 (1-38) and diaspirin cross-linked hemoglobin in rats.

Diaspirin cross-linked hemoglobin (DCLHb) is a promising hemoglobin-based, oxygen-carrying resuscitative solution. DCLHb (400 mg/kg, iv) produces significant cardiovascular effects, along with an increase in plasma endothelin-1 (ET-1) level, when administered to conscious or anesthetized rats. Present studies were performed to determine whether the cardiovascular effects of DCLHb are due to an increase in the conversion of proendothelin-1 (1-38) (proET-1) to ET-1 by endothelin-converting enzyme (ECE).

Systemic hemodynamic and regional circulatory effects of centrally administered endothelin-1 are mediated through ETA receptors.

Central endothelin (ET) has been implicated in the regulation of the cardiovascular system. The effect of intracerebroventricular (i.c.

Effect of diaspirin cross-linked hemoglobin and norepinephrine on systemic hemodynamics and regional circulation in rats.

Diaspirin cross-linked hemoglobin (DCLHb) (400 mg/kg, i.v.) produced a pressor effect that was equal to that produced by norepinephrine (NE) (25 micrograms/kg/min i.

Importance of Lyt 2+ T-cells in the curative effectiveness of a low dose of melphalan for mice bearing a large MOPC-315 tumor.

We have previously demonstrated that the curative effectiveness of a low dose (2.5 mg/kg) of melphalan (L-phenylalanine mustard; L-PAM) for mice bearing a large s.c.

Comparative effects of Pro-Leu-Gly-NH2 and cyclo(Leu-Gly) administered orally on the development of tolerance to the analgesic effect of morphine in the rat.

Comparative effects of Pro-Leu-Gly-NH2 (MIF) and cyclo(Leu-Gly) (CLG) administered orally at different stages of chronic morphine treatment on the development of tolerance to the analgesic effect of morphine in the rat were determined. Male Sprague-Dawley rats were implanted with either 6 placebo or morphine pellets during a 7-day period. Implantation of morphine pellets resulted in the development of a high degree of tolerance as evidenced by a decrease in the analgesic response to morphine.

Melphalan-induced appearance of potent antitumor immune reactivity in tumor bearer lymphocytes co-expressing the Lyt 2 and the L3T4 antigens.

We have previously shown that Sephadex G-10-adherent spleen cells from mice bearing a large MOPC-315 tumor can suppress the in vitro generation of a primary anti-MOPC-315 cytotoxic response. Here we show that following low dose melphalan (L-phenylalanine mustard; L-PAM) therapy of such tumor bearing mice their Sephadex G-10-adherent spleen cells no longer suppressed but actually brought about the generation of enhanced antitumor cytotoxicity when added to the immunization culture of normal spleen cells and MOPC-315 tumor cells. This immunopotentiating activity of the Sephadex G-10-adherent spleen cells from L-PAM treated MOPC-315 tumor bearers was attributed to T-cells which co-express the Lyt 2 and the L3T4 antigens based on results of experiments employing negative selection.