Impact of water quality on the stress physiology of cultured Labeo rohita (Hamilton-Buchanan).

Investigation was conducted for 12 months in two water bodies, S1 with optimum water quality and S2 receiving sewage water. The water quality parameters were assessed in relation to the impact on the stress sensitive physiological parameters of fish Labeo rohita. While optimum levels of transparency, dissolved oxygen, unionised ammonia, alkalinity and hardness in S1 reflected in minimum variation of the physiological parameters of L. rohita but suboptimal levels of DO (nil-18.0 mg/l) and CO2 (nil-16.0 mg/l) observed diurnally and unionised ammonia (0.11-0.42 mg/l) found throughout the experimental period, resulted in significant variation in plasma cortisol (90.0-377.0 ng/ml), cholesterol (89.6-285.0 mg/dl) and condition factor (0.7-1.3) in L. rohita. The results are of significance for fish aquatic habitat management.

Plasma cortisol levels in captive wild felines after chemical restraint

Eight Panthera onca (Po), 13 Felis concolor (Fc), Felis yagouaroundi (Fy) 7 Felis tigrina (Ft) and 5 Felis pardalis (Fp) specimens from SÒo Paulo State zoos were used. All animals were restrained with darts containing 10 mg/kg ketamine and 1 mg/kg xylazine. Venous blood samples were collected as soon as possible (within 15-20 min) and serum was frozen until the time for cortisol quantification. Cortisol was determined using a solid phase radioimmunoassay with and intra-assay coefficient of 8.51 percent. Data were analyzed statistically by the Kruskal-Wallis test, followed by Dunn´s multiple comparisons test, and the one-sample t-test, with the level of significance set at P<0.05. Data are reported as means + SEM. Cortisol levels differed among the captive felines: Po = 166 + 33a, Fc = 670 + 118b, Fy = 480 + 83b, Ft = 237 + 42ab, Fp = 97 + 12a nmol/l (values followed by different superscript letters were significantly different (P<0.001). Since most of the veterinary procedures on these species involve chemical restraint, these results show the necessity of preventive measures in order to minimize the effect of restraint stress on more susceptible species.

Interrelationship between amines level in brain regions of fish, Oreochromis mossambicus during organophosphorus stress.

Amines such as dopamine, norepinephrine and epinephrine were analysed in the brain regions of O.mossambicus exposed to quinalphos, phenthoate and their combination for 96 hr. The three types of treatments significantly (P < 0.05) altered the amines level at various intervals in the brain regions.

How safe is adenosine when used as a pharmacologic stressing agent in myocardial perfusion scintigraphy?

Myocardial perfusion imaging is used in the assessment of coronary artery disease by stressing patients either physically or pharmacologically. Adenosine was used as a pharmacologic stressor when administered at a dose of 0.14 mg/kg/min for 6 min to determine its safety at this dose level. Twenty patients referred for myocardial perfusion imaging were stressed with adenosine. The protocol was completed in 18 patients; 1 patient needed early termination of the infusion while another patient needed dose reduction. There patients did not experience any side effects and 17 patients experienced side effects that were short-lived. All the patients showed good tolerance to the test. Hence adenosine is a safe pharmacologic stressor at this dose level for myocardial perfusion imaging

Vías metabólicas en el músculo cardíaco de ratas sometidas a estress hipobárico / Metabolic pathway in the myocardial tissue of rats under hypobaric stress

En el presente trabajo se han estudiado tres vías de producción de energía en el músculo cardíaco de ratas con hipoxia hipobárica: La glicólisis anaeróbica, representada por el ácido láctico, la fosforilación oxidativa a través de la actividad de la ICD y la utilización de los cuerpos cetónicos a través de la 3-HBD. Simultáneamente se estudió el papel de la CK citoplasmática y mitocondrial como sistemas de conexión y trasnporte de energía entre las fuentes de producción y su utilización por las ATPasa Mg++ y Na+K+ dependientes. Los hallazgos obtenidos permiten concluir que existe una activación de la glicólisis y una mayor utilización de los cuerpos cetónicos, en los animales hipóxicos tal como se deduce del aumento del ácido láctico y de la actividad de la 3-HBD. Esto se correlaciona con el aumento de la CK de origen citoplasmático, lo cual se asocia con la glicólisis y una disminución de la CK de origen mitocondrial. En cuanto a la utilización de la energía, ésta probablemente se encuentra derivada en mayor porcentaje hacia el control del flujo iónico, tal como se deduce del aumento de la actividad de la ATPasa Na+K+ dependiente en mayor proporción que la Mg++ dependiente.

Effect of a specific stress (aldrin) on rat progeny behavior

The effect of dam exposure to aldrin, an organochlorinated compound (1.0 mg/Kg, sc, daily), during pregnancy or lactation was studied in young tat pups (11, 15, 18 and 22 days of age) and in adult animals (90 days of age). Locomotor activity was significantly greater in both young and adult animals when compared to contols. Male rats that received aldrin during lactation also showed reduced plasma corticosterone levels. Maternal behavior was not affected bu treatment during either period. The results sugest that aldrin may act as a perinatal stress factpr

Efeito do estresse agudo provocado pela nicotina sobre o fígado da rata prenhe e de seus conceptos, previamente tratados com diferentes doses de propranolol: estudo histológico e ultra-estrutural / Effect of acute stress induced by nicotine on the liver of pregnant rats and embryos previously treated with propronolol: an ultrastructural and histological study

Realizou-se em ratas albinas prenhes um trabalho experimental a respeito do efeito do estresse agudo sobre o fígado materno e fetal, assim como análise do efeito antagonista do propranolol nessa situaçäo. A nicotina foi usada como agente alarmógeno, e o estudo do tipo morfológico foi realizado a nível de microscopia óptica e eletrônica. Verificou-se que, tanto o fígado materno quanto o fetal, apresentaram alteraçöes histológicas (corpúsculos de Councilman, hiperplasia das células de Kupffer, focos de necrose) e ultra-estruturais (vacuolizaçäo mitocondrial, dilataçäo do REL, infiltraçäo lipídica, depleçäo glicogênica) desencadeadas pelo estresse agudo. O cloridrato de propranolol, por seu efeito beta-bloqueador, foi capaz de atenuar as alteraçöes morfológicas verificadas nos fígados materno e fetal, e provocados pelo estresse agudo