Several investigators have demonstrated that streptozotocin (STZ) diabetes induces changes in the autonomic control of the cardiovascular system. Changes in cardiovascular function may be related to peripheral neuropathy. The aim of the present study was to analyze changes in heart rate (HR) and arterial pressure (AP) as well as baroreflex and chemoreflex sensitivity in STZ-induced diabetic male Wistar rats (STZ, 50 mg/kg, iv, 15 days). Intra-arterial blood pressure signals were obtained for control and diabetic rats (N = 9, each group). Data were processed in a data acquisition system (CODAS, 1 kHz). Baroreflex sensitivity was evaluated by measuring heart rate changes induced by arterial pressure variation produced by phenylephrine and sodium nitroprusside injection. Increasing doses of potassium cyanide (KCN) were used to evaluate bradycardic and pressor responses evoked by chemoreflex activation. STZ induced hyperglycemia (447 ± 49 vs 126 ± 3 mg/dl), and a reduction in AP (99 ± 3 vs 118 ± 2 mmHg), resting HR (296 ± 11 vs 355 ± 16 bpm) and plasma insulin levels (16 ± 1 vs 57 ± 11 µU/ml). We also observed that the reflex bradycardia (-1.68 ± 0.1 vs -1.25 ± 0.1 bpm/mmHg, in the diabetic group) and tachycardia (-3.68 ± 0.5 vs -1.75 ± 0.3 bpm/mmHg, in the diabetic group) produced by vasopressor and depressor agents were impaired in the diabetic group. Bradycardia evoked by chemoreflex activation was attenuated in diabetic rats

Significant agreement was found between the four most recent guidelines. Abdominal obesity cut-off points might support differences agreement differences.

RESUMEN.Se evaluó el efecto de seis temperaturas constantes en la sobrevivencia embrionaria, periodo embrionario y periodo de eclosión de Galaxias maculatus de 7 a 22ºC, en condiciones de laboratorio. Los resultados de la sobrevivencia embrionaria fueron: 90,6 ± 2,0; 88,7 ± 8,6; 87,7 ± 0,7; 89,7 ± 4,2; 70,0 ± 5,6 y 49,5 ± 7,4% a temperaturas de 7, 10, 13, 16, 19 y 22ºC. Exceptuando la temperatura de 22ºC, no hay diferencias significativas entre ellas (P > 0,05). Estos resultados caracterizan al embrión como euritérmico independientemente de ser una especie de aguas subantárticas. En relación al periodo embrionario (ʈʜ50%), los resultados fueron de 40,8 ± 0,6; 27,0 ± 0,0; 17,3 ± 0,6; 16,3 ± 0,6 y 13,3 ± 0,6 días a temperaturas de 7, 10, 13, 16 y 19ºC respectivamente, con diferencias significativas entre ellas (P < 0,05), y en el caso del periodo de eclosión (ʈʜ50%), fue de 8,3 ± 0,6; 6,3 ± 1,5; 5,0 ± 0,0; 6,3 ± 0,6; 5,0 ± 1,0 y 4,3 ± 0,6 días a temperaturas de 7, 10, 13, 16, 19 y 22ºC respectivamente, con diferencias significativas entre ellas (P < 0,05). Los resultados sugieren que el rango de temperaturas entre 10 y 16°C es óptimo para la incubación de ovas de G. maculatus, ya que se obtienen combinadamente altos porcentajes de sobrevivencia embrionaria >87,7%, periodos embrionarios <27 días y periodos de eclosión <6,3 días. Estos resultados permitirán optimizar la sobrevivencia embrionaria y el eventual cultivo de la especie para fines comerciales o de repoblamiento. Palabras claves: Galaxias maculatus, puye, eclosión, incubación, tolerancia térmica, sobrevivencia embrionaria. Effect of temperature on survival of embryos of puye Galaxias maculatus(Jenyns, 1842) ABSTRACT. We evaluated the effect of six constant temperatures on embryonic survival, embryonic period and hatching period of Galaxias maculatus from 7 to 22°C under laboratory conditions. The results of embryo survival were: 90.6 ± 2.0, 88.7 ± 8.6, 87.7 ± 0.7, 89.7 ± 4.2, 70.0 ± 5.6 and 49.5 ± 7.4% at temperatures of 7, 10, 13, 16, 19 and 22ºC. Except for the temperature of 22°C, there were no significant differences between them (P < 0.05). These results characterize the embryo as eurythermic regardless of being a subantarctic waters species. Regarding the embryonic period (ʈʜ50%), the results were 40.8 ± 0.6, 27.0 ± 0.0, 17.3 ± 0.6, 16.3 ± 0.6 and 13.3 ± 0.6 days at temperatures of 7, 10, 13, 16 and 19°C respectively, with significant differences between them (P < 0.05) and in the case of the hatching period (ʈʜ50%), was 8.3 ± 0.6, 6.3 ± 1.5, 5.0 ± 0.0 and 6.3 ± 0.6, 5.0 ± 1.0 and 4.3 ± 0.6 days at temperatures of 7, 10, 13, 16, 19 and 22ºC respectively with significant differences between them (P < 0.05). These results suggest that the range of temperatures between 10 and 16°C is optimal for the incubation of G. maculatus eggs, since in that range high embryonic survival (>87.7%) combined with embryonic periods of less than 27 days and hatching periods less than 6.3 days were obtained. These results will optimize embryo survival and eventually reari...

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