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Concentration and seasonal variations of acetylcholine in sleep and waking dialysates

1972; Elsevier BV; Volume: 11; Issue: 4 Linguagem: Inglês

10.1016/0028-3908(72)90003-2

1873-7064

M Monnier, B. Herkert,

Mindfulness and Compassion Interventions

The concentrations of acetylcholine (ACh) were determined in the haemodialysate of rabbits kept experimentally asleep, during extracorporeal dialysis, by stimulating the medio-ventral thalamus, or kept aroused by stimulating the midbrain reticular system. The investigations were performed over 2 yr in order to study the biorhythmic seasonal variations. The dialysates were grouped according to their donors in the following categories: aroused, sleep-resistant (alert or slightly stressed) donors, sleeping and control donors. The concentration of acetylcholine was significantly increased in the donors aroused by stimulation of the reticular system (68.7±4 ngml), whereas in sleep-resistant donors (42.0±9 ngml) and sleeping donors it increased only during the summer. The curve of the ACh concentration was well correlated with the curve of the external daily temperature, both showing a minimum in the winter and a maximum in the summer. This supports the concept of a cholinergic waking mechanism, possibly mediated by the projections ascending from the activating midbrain reticular system to subcortical and cortical structures.