Abstract |
1. The effects of a noradrenaline precursor, L-threo-3,4-dihydroxyphenylserine (L-DOPS), on spinal mono-(MSR) and polysynaptic reflexes (PSR) and decerebrate rigidity, were studied. 2. Although a low dose of L-DOPS (10 mg/kg, i.v.) did not affect MSR or PSR in C1 spinal rats, high doses of L-DOPS (50 and 100 mg/kg, i.v.) moderately enhanced the amplitudes of both MSR and PSR. 3. Clorgyline-HCl (1 mg/kg, i.v.), an MAO inhibitor, enhanced the excitatory effects of low-dose L-DOPS (10 mg/kg, i.v.) on both reflexes. 4. Benserazide-HCl (1 mg/kg, i.v.), an L- aromatic amino acid decarboxylase inhibitor, decreased the pressor effect, but not the stimulatory effects, of L-DOPS (100 mg/kg, i.v.) on MSR and PSR. 5. L-DOPS (300 mg/kg, i.p. or i.d.) did not affect the muscle tone of rigid hindlimbs caused by radio frequency lesioning of the midbrain. 6. These results suggest that the moderate enhancing effects of L-DOPS on MSR and PSR are due to conversion of L-DOPS to noradrenaline in the spinal cord.
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Authors | H Ono, M Tanabe, T Nakamura, N Nagano, H Fukuda |
Journal | General pharmacology
(Gen Pharmacol)
Vol. 19
Issue 3
Pg. 369-72
( 1988)
ISSN: 0306-3623 [Print] England |
PMID | 3138156
(Publication Type: Journal Article)
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Chemical References |
- Serine
- Benserazide
- Droxidopa
- Clorgyline
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Topics |
- Animals
- Benserazide
(pharmacology)
- Blood Pressure
(drug effects)
- Clorgyline
(pharmacology)
- Decerebrate State
(physiopathology)
- Droxidopa
(antagonists & inhibitors, pharmacology)
- Male
- Motor Activity
(drug effects)
- Rats
- Rats, Inbred Strains
- Reflex
(drug effects)
- Serine
(analogs & derivatives)
- Spinal Cord
(drug effects)
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