RESUMO
Median third eye was found to develop from transplanted pineal gland of external gill stage tadpoles in the recipient 5 toe stage tadpoles of Bufo melanostictus. Pineal gland along with a bit part of brain tissue of the donor external gill stage tadpole was cut out and transplanted into a pit made between two lateral eyes of 5 toe stage recipient tadpoles. Half of the operated tadpoles were treated with vitamin A (15 IU/ml.) for 15 days. Median "third eye" was found to develop in the both untreated and vitamin A treated tadpoles. However, vitamin A increased the percentage of the development of median eyes. Morphological and histological study revealed that newly transformed median eyes were similar to that of normal functional eyes. A stalk like structure developed which connects the median eye to the brain. The median third eye could not develop when pineal gland of 5 toe stage mature tadpole was transplanted into the tadpole of the same age.
Assuntos
Animais , Bufonidae/crescimento & desenvolvimento , Olho/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Morfogênese/efeitos dos fármacos , Glândula Pineal/efeitos dos fármacos , Vitamina A/farmacologiaRESUMO
After removal of both the lateral eyes of external gill stage tadpoles of the toad Bufo melanostictus, the pineal organ gets transformed into a median eye. This type of transformation occurs in tadpoles of both control and vitamin A treated groups. However, vitamin A increases the likelihood of homeotic regeneration (57% in the control group and 71% in the vitamin A treated group). Histological studies showed that the newly transformed median eye developed from the pineal organ. The pineal eye so developed possessed all components of a normal eye such as a retina, sensory cells and lens.
Assuntos
Animais , Bufonidae/crescimento & desenvolvimento , Genes Homeobox , Larva/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Vitamina A/farmacologiaRESUMO
Electropolarity treatment (0.8V/DC/Cm) was given to the gastrocnemius muscle of B. melanostictus every day for 5 min for 5 days. The glycogen content and aldolase activity levels increased and phosphorylase 'a' activity levels decreased on cathode treatment in muscle, liver and brain while an opposed trend was observed on anode treatment. The heart showed contrasting pattern under both cathode and anode electropolarity treatments.
Assuntos
Animais , Encéfalo/metabolismo , Bufonidae , Estimulação Elétrica , Glicogênio/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Miocárdio/metabolismoRESUMO
Denervated dog gastrocnemius muscle has shown a progressive decrease in total protein content, alanine aminotransferase (AIAT), aspartate aminotransferase (AAT) and glutamate dehydrogenase (GDH) activity levels and elevation in free amino acid, ammonia, urea, glutamine contents and AMP deaminase activity levels during post-neurectemic days. The possible implications of these findings are discussed in relation to denervation atrophy.
Assuntos
Alanina Transaminase/metabolismo , Aminoácidos/metabolismo , Amônia/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Cães , Glutamato Desidrogenase/metabolismo , Denervação Muscular , Proteínas Musculares/metabolismo , Músculos/metabolismo , Atrofia Muscular/metabolismo , Ureia/metabolismoRESUMO
Glutamate dehydrogenase (GDH) and the transaminases namely aspartate aminotransferase (AAT) and alanine aminotransferase (AIAT) were estimated in the muscle, liver, kidney, and brain of control and ammonium acetate administered frogs. The results indicated tissue specific responses during induced ammonotoxemia. The inherent endogenous ammonia production decreased in all the tissues. 2-Keto glutarate production appears to be the other main adaptive feature as a result of slightly stepped up transdeamination patterns.
Assuntos
Alanina Transaminase/análise , Amônia/metabolismo , Animais , Aspartato Aminotransferases/análise , Glutamato Desidrogenase/análise , Glutamina/análise , RanidaeRESUMO
In the sheep medulla oblongata, on the induction of polarity by the applied voltage gradient of direct current along the length, the enzymes such as acetylcholinesterase and glutamate dehydrogenase showed anodal transport while the enzyme arginase showed cathodal transport indicating the possession of negative and positive charge densities on the enzymes. These studies indicated that the glutamate bound metabolism, one towards ammonia formation and the other towards the energy production and neural transmission, have opposed electro-characteristics. The acetylcholinesterase system had anodal characteristics coupled to the glutamate dehydrogenase patterns. The existence of two charge based compartmentation is envisaged in the neural tissue.
Assuntos
Acetilcolinesterase/metabolismo , Animais , Arginase/metabolismo , Transporte Axonal , Estimulação Elétrica , Eletrofisiologia , Glutamato Desidrogenase/metabolismo , Bulbo/fisiologia , Ovinos/fisiologia , Transmissão SinápticaRESUMO
Different ammonia toxicity induced by ammonium acetate administration in frogs lead to variable excretion of ammonia and urea into the medium. When 11.45 mM/kg body weight of ammonium acetate was administered, ammonia excretion increased while urea excretion decreased. When 4.17 mM/kg body weight of ammonium acetate is administered, the urea excretion increased while ammonia excretion decreased. The possible metabolic conversion of ammonia and urea by the animal at high and low ammonium acetate administration has been discussed.