Biomedical subjects

S M Baser

Publications and source records attributed to S M Baser.

4 recordsLinked to original sources

PubMed1991

Antibody in the CSF of patients with multiple system atrophy reacts specifically with rat locus ceruleus.

Idiopathic chronic autonomic dysfunction may occur as pure autonomic failure (PAF) or in association with multiple system atrophy (MSA). CSF immunoreactivity to rat locus ceruleus occurred in a significantly greater number of samples from MSA patients compared to control subjects or patients with PAF. Other brain regions infrequently showed immunoreactivity. These findings suggest that degeneration in MSA may release antigen(s) that induce antibodies against locus ceruleus neurons. Further studies are required to determine whether immune abnormalities play a pathogenetic role in MSA. Lack of CSF immunoreactivity in PAF is consistent with primarily peripheral involvement.

Adult↗

PubMed1991

Central and peripheral effects of arecoline in patients with autonomic failure.

Increased plasma adrenalin (A) levels following arecoline in normal subjects and patients with multiple system atrophy (MSA) may result from nicotinic adrenal stimulation. Lack of this response in patients with pure autonomic failure (PAF) is consistent with peripheral sympathetic dysfunction. The mechanisms underlying diminished plasma corticotropin (ACTH) responses to arecoline may differ in patients with autonomic failure. Hypothalamic, cholinergic degeneration could prevent the response in MSA whereas patients with PAF do not manifest the normal increase in A which may be required to elicit an ACTH response. The appearance and exacerbation of tremor, vertigo, and pathological affect in the MSA group suggest that some central cholinergic receptors remain functional.

Adrenocorticotropic Hormone↗

PubMed1991

Sudomotor function in autonomic failure.

We measured sweat production to direct gland stimulation with intradermal methacholine in patients with autonomic failure and in normal subjects. The sympathetic skin response (SSR) to electrical stimulation was assessed in some of the same subjects. Patients with pure autonomic failure (PAF) and multiple system atrophy (MSA) produced significantly less sweat than controls. None of the patients manifested greater than normal sweat production. Impaired sweat gland function does not differentiate MSA and PAF. The SSR did not correlate with sweat response to methacholine. An SSR can occur in the absence of normal sweat gland function. The diminished production of sweat in response to intradermal methacholine in PAF suggests that human sweat glands do not develop chronic denervation supersensitivity. Intradermal methacholine is a simple method to assess sweat gland function.

Adult↗

PubMed1991

Beta-receptor sensitivity in autonomic failure.

We examined the cardiovascular, plasma norepinephrine (NE), and plasma renin (PRA) responses to isoproterenol infusion in patients with autonomic failure and in normal subjects. Slopes of the blood pressure response/dose relationships were more negative in patients with multiple system atrophy and pure autonomic failure (PAF) than in normal subjects, consistent with impaired baroreflex modulation. A shift to the left in patients with PAF suggests beta-adrenergic receptor supersensitivity. In normal subjects, the increase in plasma NE and PRA was proportional to the log of the plasma isoproterenol level. Isoproterenol infusion did not increase plasma NE or PRA in either patient group despite a reduction in mean blood pressure. Reflexive cardiovascular and renal mechanisms appear to play a role in eliciting the plasma NE and PRA responses to isoproterenol infusion in normal subjects.

Autonomic Nervous System Diseases↗