Local blood flow in the thalamus and frontal cortex in alert and narcotized dogs.

The magnitude of the local blood flow in the thalamus and cerebral cortex is studied on 22 sexually mature nonpedigree dogs. Mean values of local blood flow are obtained in alert animals, and the effect of narcosis (nitrous oxide) on the local cerebral blood flow is studied. The mean local blood flow in alert dogs is found to be 84.8 +/- 2.9 ml/100 g/min in the cerebral cortex and 68.7 +/- 1.6 ml/100 g/min in the thalamus. Insignificant fluctuations are found during a dynamic recording of the local blood flow during 7 days. Under narcosis (70% nitrous oxide) the local blood flow decreases 3-12%. According to the findings, nitrous oxide narcosis does not significantly affect the brain circulation, so that it is suitable for an experimental study of the latter.

[Local blood flow in the optic thalamus and frontal lobe in conscious and anesthetized dogs]. / Mestnyi krovotok v zritel'nom bugre i lobnoi kore u bodrstvuiushchikh i narkotizirovannykh sobak.

Control values of local blood flow in the thalamus of alert dogs were 68.7 +/- 1.6 ml/100g/min and in their frontal cortex 84.8 +/- 2.9 ml/100 g/min. As a result of the hexenal anesthesia, the local blood flow decreased by 3 to 12 per cent of control values. The mild effect suggests that the anesthesia maintained with the 70% N2O is an acceptable procedure for studying the cerebral circulation.