Application of an ultraviolet (UV) spectroscopic method for measuring lipoprotein cholesterol in diabetic hypothyroid rats.

Methods for the isolation and quantitation of cholesterol involve time-consuming chromatographic procedures coupled with the development and measurement of color complexes. The intensity of most color complexes varies with time. This study was undertaken to develop a UV spectrophotometric method to measure cholesterol concentration in plasma lipoprotein fractions.

Research centers on minority institutions (RCMI): II.

The goal of the Research Centers in Minority Institutions (RCMI) is to develop biomedical and behavioral research at institutions with 50% minority enrollment (African Americans, Hispanics, Native Hawaiians, Pacific Islanders, Native Americans and Alaska Natives) who have been underrepresented in the biomedical sciences. The program has made available resources vital to scientific development and progress. While these resources have included, equipment, personnel supplies, Core laboratories etc, important effective approaches to research also have been emerging.

The effect of regular alcohol use on the management of non-insulin diabetes mellitus.

This is a retrospective study, in which we investigated the impact of regular alcohol use on the clinical management of non-insulin dependent diabetes mellitus (NIDDM) patients from the outpatient clinic of the VA Medical Center in New Orleans, Louisiana. The study population included randomly selected NIDDM patients of which 40% used alcohol regularly. The fasting blood sugar (FBS) in non-users of alcohol stayed in the "normal" (< or = 140 mg/dl) and "acceptable " (< or = 175 mg/dl) range and that of regular users of alcohol remained at the "fair" (< or = 235 mg/dl) and "poor" (> 235 mg/dl) range.

Research Centers in Minority Institutions (RCMI).

The Research Centers in Minority Institutions (RCMI) Program was initiated in the United States of America in 1985 as a congressionally mandated program. The mission of the RCMI Program is to expand the national capacity for the conduct of biomedical and behavioral research by developing the research infrastructure at institutions granting doctoral degrees in health or health-related sciences, that have 50% or greater enrollment of minorities (African Americans, Hispanics, Native Hawaiians and Pacific Islanders, Native Americans and Alaska Natives) that are underrepresented in the biomedical sciences. The program administration is based in the National Center for Research Resources (NCRR), at the National Institutes of Health (NIH), an agency of the Department of Health and Human Services (DHHS).

Evidence for the interaction of protein kinase C and melanocortin 3-receptor signaling pathways.

The melanocortin-3 receptor, MC3-R, is abundant in the brain and is activated by gamma-2-melanocyte stimulating hormone (gamma-2-MSH). We have previously reported the translocation of protein kinase C (PKC) in spontaneous hypertensive rat (SHR) brain synaptosomes treated with gamma-2-MSH. In this study, the expression of PKA and the related PKB in SHR brain synaptosomes was analyzed.

Expression and distribution of protein kinase C isozymes in brain tissue of spontaneous hypertensive rats.

Hypertension activates many endocrine, neuroendocrine and metabolic responses. How hypertension alters these functions remains unknown. Consequently the pathophysiology of hypertension related illnesses are incompletely understood.

Effects of gamma-2-melanocyte-stimulating hormone on protein kinase C activity and expression in spontaneous hypertensive rats (SHR).

Administration of gamma-2-melanocyte stimulating hormone (gamma-2-MSH) to rats increases blood pressure, heart rate and natriuresis by acting through the nervous system and this response is more pronounced in spontaneous hypertensive rat (SHR). The molecular mechanisms underlying these effects are unknown, however, protein kinase C (PKC) activity is higher in SHR tissues and melanocortins are known to activate the phosphoinositide (PI) signaling pathway. In this study, we tested the hypothesis that gamma-2-MSH potentiation of PKC activation is increased in nerve terminals from SHR brain.

Isolation of cholinergic active ingredients in aqueous extracts of Mareya micrantha using the longitudinal muscle of isolated guinea-pig ileum as a pharmacological activity marker.

In our attempt to isolate the pharmacologically active ingredients in the aqueous extracts of Mareya micrantha, we have selected the contractions of the longitudinal muscle of the isolated guinea-pig ileum preparation as a pharmacological marker to monitor retention of pharmacological activity during the chromatographic separation. The aqueous extracts of Mareya micrantha elicited concentration-dependent contractions of the preparation. The maximum response elicited by the aqueous extracts was 50% of the maximum response elicited by the maximum dose of acetylcholine (ACh), 10(-7) M.

The use of isolated functional heart to pharmacologically characterize active ingredients in the aqueous extracts of Mareya micrantha.

Aqueous extracts of Mareya micrantha are used as folk medicine in West Africa. However, no systemic investigation directed to the identification of the active ingredients in M. micrantha has been done.

The effects of stress on lipoproteins and catecholamines in rats.

In order to investigate the effects of transportation stress on metabolic activities, we measured the changes in plasma lipoprotein and catecholamine levels in those rats that had just arrived in our Animal Facility and age-matched rats which had acclimatized in the Facility for at least 21 days. The acclimatized rats were considered as control, and the values from the newly arrived rats was done within 4-6 days of their arrival in the Facility. The cholesterol levels in very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) were higher (71-84%) than the control levels.

Autoradiographic demonstration of the distribution of diacylglycerol in the gastric muscularis muscle of Bufo marinus: is diacylglycerol one of the second messengers in the muscularis muscle?

The distribution of 1,2-diacylglycerol (DAG) in the muscularis muscle of Bufo marinus has been determined using autoradiographic techniques. Strips of the muscle from the body of the stomach were fixed in 4% paraformaldehyde/2.5% glutaraldehyde, postfixed, washed and longitudinal sections (15 microns) were cut on a cryotome and placed on gelatinized slides.

Cassia alata and the preclinical search for therapeutic agents for the treatment of opportunistic infections in AIDS patients.

In our search for therapeutic agents from natural sources with potential for the treatment of opportunistic infections in patients afflicted with acquired immunodeficiency syndrome (AIDS), we investigated antibacterial and antifungal activities of water extracts of Cassia alata (C. alata). The extracts are traditionally used in Ivory Coast, West Africa to treat bacterial infections caused by Escherichia coli (E.

Cassia alata and the preclinical search for therapeutic agents for the treatment of opportunistic infections in AIDS patients.

In our search for therapeutic agents from natural sources with potential for the treatment of opportunistic infections in patients afflicted with acquired immunodeficiency syndrome (AIDS), we investigated antibacterial and antifungal activities of water extracts of Cassia alata (C. alata). The extracts are traditionally used in Ivory Coast, West Africa to treat bacterial infections caused by Escherichia coli (E.

Pharmacological effects of berberine on the longitudinal muscle of the guinea-pig isolated ileum.

The effects of berberine on the contractions of the longitudinal muscle of the guinea-pig isolated ileum were investigated. Lower concentrations of berberine (less than or equal to 5 x 10(-5) M) induced a parallel rightward shift of the dose-response curve of acetylcholine, suggesting that berberine is antagonizing the actions of acetylcholine at the receptors competitively. At higher concentration, berberine (1 x 10(-4) M) facilitated a rightward shift of the dose-response curve of acetylcholine with a reduction of maximum response, indicating that the interactions of the two agents changed from competitive to noncompetitive antagonism.

Cardiovascular effects of doxorubicin.

1. Doxorubicin dose-dependently increased the cardiac contractility of isolated frog heart within the dose-range of 1.0 to 10.

Low temperature and muscarinic receptor activities.

Lowering temperature from 37 degrees C to 22, 18, and 14 degrees C triggered automaticity of smooth longitudinal muscle of guinea pig isolated ileum. The amplitude of the hypothermia-induced automaticity was dependent on the degree of temperature drop: the greater the temperature drop, the greater the amplitude. However, when the preparation was initially prepared and maintained at 14 degrees C and then the temperature was raised at a similar rate to 18, 22, and 37 degrees C, the automaticity was not observed.

A comparative study of the effects of aging on the responsiveness of the cholinergic receptor of the isolated ileum of mouse and rat.

The responsiveness of the cholinergic receptor (ChR) of the isolated ileum of mouse and rat was characterized by determining the ED50 of acetylcholine (ACh) and pA2 of mepenzolate (MPZ) in tissues from animals of different ages. The ages (in months) of mice were 3, 6 and 18 and; 3, 6, 12 and 24 for rats respectively. The responsiveness of ChR in mice and rats decreased with age.

The effects of hypothermia on the blockade of muscarinic receptors by phenoxybenzamine.

To characterize the hypothermia-induced changes in the activity and kinetic constants for muscarinic receptors, we investigated the effects of hypothermia on the onset and offset of action of phenoxybenzamine from the muscarinic receptors of the longitudinal muscle of the guinea-pig isolated ileum. At 37 degrees C, the onset of phenoxybenzamine action was very rapid (less than 5 min) and there was no apparent recovery of the response to ACh 70 min after washing off the phenoxybenzamine. However, the onset at 24 degrees C was very slow (30 min) and there was a complete recovery of the response to ACh 40 min after washing off the unoccluded phenoxybenzamine.

The effects of phenylbutazone on acetylcholine-initiated contractions of gastric muscularis muscle of Bufo marinus.

We have investigated the effects of phenylbutazone (PBZ), a potent prostaglandin (PG) synthesis inhibitor, on the acetylcholine (ACh)-initiated contractions of isolated gastric muscularis muscle of Bufo marinus. Two types of contractions were identified: tonic contractions and spontaneous contractions. The challenging dose of ACh (1.

The effects of aging on the responsiveness of the cholinergic receptor of the longitudinal muscle of guinea-pig isolated ileum.

The responsiveness of the cholinergic receptor (ChR) of the longitudinal muscle of guinea-pig isolated ileum was characterized by determining the ED50 of acetylcholine (ACh) and pA2 of mepenzolate (MPZ) in tissues from animals of different ages. The ages of guinea pig were 0.75, 3, 6 and 24 months respectively.

Characterization of cholinesterase of muscularis muscle of Bufo marinus.

We have characterized the cholinesterase (ChE) of muscularis muscle of Bufo marinus by selectively using specific inhibitors of acetylcholinesterase and pseudocholinesterase and observing susceptibility to inhibition when substrate is present in excess. The ChE activity in this preparation due to acetylcholinesterase (AChE) and pseudocholinesterase (BuChE) was 90 and 10%, respectively. The optimum temperature and pH for the ChE were 38 degrees C and 7.

The influence of prostaglandin E2 (PGE2) on the acetylcholine-initiated contractions of isolated gastric muscularis muscle of Bufo marinus.

Acetylcholine (ACh) (1.5 X 10(-5) M) elicited three different types of tonic and phasic contraction of muscularis muscle from different parts (cardiac, middle and pyloric) of the stomach of Bufo marinus. Prostaglandin E2 (PGE2) (10(-9)-10(-6) M) induced a concentration-dependent relaxation of tonic contractions elicited by ACh (1.

Comparative studies of cardiovascular effects of a new dopamine agonist (SK&F 38393A) and dopamine.

SK&F 38393A (DAA) dose-dependently decreased the contractility of isolated frog hearts with an ED50 of 6.60 +/- 0.28 X 10(-5) M, while, dopamine (DA) elicited a dose-dependent increase in the contractility of the preparation with an ED50 of 5.

Preliminary pharmacological characterization of the isolated circular strips of gastric muscularis muscle of Bufo marinus: a new preparation.

This paper describes a preliminary pharmacological study of isolated circular strips of gastric muscularis muscle of Bufo marinus under isometric conditions. The stomach of Bufo marinus was surgically removed and the muscularis muscle was isolated and divided into 12 equal parts from the fundus to the pylorus. The preparation contracted to acetylcholine (ACh), DL-muscarine, and K+.