Pontine tegmentum

Garzon, M., De Andres, I. Reinoso-Suarez, F. (1998). Sleep patterns after carbachol delivery in the ventral oral pontine tegmentum of the cat. Neuroscience 83, 1137-44. 

Henley, K. 8r Morrison, A. R. (1974). A re-evaluation of the effects of lesions of the pontine tegmentum and locus coeruleus on phenomena of paradoxical sleep in the cat. Acta Neurobiol. Exp. (Wars). 34, 215-32. 

Singh, S. Mallick, B. N. (1996). Mild electrical stimulation of pontine tegmentum around locus coeruleus reduces rapid eye movement sleep in rats. Neurosci. Res. 24, 227-35. 

Tononi, G., Pompeiano, M. Cirelh, C. (1991). Suppression of desynchronized sleep through microinjection of the alpha 2-adrenergic agonist clonidine in the dorsal pontine tegmentum of the cat. Pflugers Arch. 418, 512-18. 

Baghdoyan, H. A., Rodrigo-Angulo, M. L., McCarley, R. W. Hobson, J. A. (1987). A neuroanatomical gradient in the pontine tegmentum for the cholinoceptive induction of desynchronized sleep signs. Brain Res. 414, 245-61. 

Local administration of the Hi agonist 2-thiazolylethylamine (50 pg in 0.5 pi) into the pontine tegmentum increased wakefulness and reduced NREM sleep during the first 3 h after injection. In contrast, local application of mepyramine (5 pg in 0.25 pi) caused a decrease in wakefulness and an increase in NREM sleep. 

Administration of H2-receptor agonists and antagonists in rats had no effect on sleep-wakefulness (Monti et al., 1986,1990). Although local application of impromidine (1 pg in 1 pi), an H2 receptor agonist, into the preoptic region of the cat mimicked the effects of HA in inducing wakefulness, local application of impromidine (0.2 pg in 0.25 pi) in the pontine tegmentum had little effect. 

How and why is the limbic forebrain selectively activated in REM so as to produce this kind of affective experience The how answer is that in addition to its major cholinergic innervation from the basal forebrain the limbic area receives a direct projection from the dorsolateral pontine tegmentum, where the cholinergic neurons that become selectively active in REM sleep are found in animals. PET studies can t yet tell us if this particular brain stem region is selectively activated in human REM sleep, but we hypothesize that such a homology is likely. 

Bourgin P, Lebrand C, Escourrou P, Gaultier C, Franc B, Hamon M, Adrien J. Vasoactive intestinal polypeptide microinjections into the oral pontine tegmentum enhance rapid eye movement sleep in the rat. Neuroscience 1997 77 351-60. 

Bourgin P, Ahnaou A, Laporte AM, Hamon M, Adrien J. Rapid eye movement sleep induction by vasoactive intestinal peptide infused into the oral pontine tegmentum of the rat may involve muscarinic receptors. Neuroscience 1999 89 291-302. 

Infarction of the medial pontine tegmentum will cause coma and is a poor prognostic sign (Fisher 1977 Kataoka et al. 1997). 

Initially, there is a confused state, Korsakoff s psychosis, that is characterized by confabulation and loss of recent memory, although memory for past events may be unimpaired. Later, clear neurological signs develop - Wernicke s encephalopathy. This is characterized by nystagmus and extraocular palsy. Postmortem examination shows hemorrhagic lesions in the thalamus, pontine tegmentum, and mammillary body, with severe damage to astrocytes, neuronal dendrites, and myelin sheaths. 

Liu RH, Fung SJ, Reddy VK, Barnes CD (1995) Localization of glutamatergic neurons in the dorsolateral pontine tegmentum projecting to the spinal cord of the cat with a proposed role of glutamate on lumbar motoneuron activity. Neuroscience 64 193-208. 

Chu N-S, Bloom FE (1974) The catecholamine-containing neurons in the cat dorsolateral pontine tegmentum distribution of the cell bodies and some axonal projections. Brain Res, 66, 1-21. 

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