PMID- 1674894
OWN - NLM
STAT- MEDLINE
DCOM- 19910711
LR  - 20190613
IS  - 0006-8993 (Print)
IS  - 0006-8993 (Linking)
VI  - 544
IP  - 2
DP  - 1991 Mar 29
TI  - Microinjections of norepinephrine into the intermediolateral cell column of the 
      spinal cord exert excitatory as well as inhibitory effects on the cardiac 
      function.
PG  - 227-34
AB  - Cardiac responses to microinjections of norepinephrine (NE) into the 
      intermediolateral column of the spinal cord (IML) at T2 level were studied in 
      pentobarbital-anesthetized, immobilized and artificially ventilated, male Wistar 
      rats. For describing the effects of NE conveniently, the doses of NE were divided 
      into two ranges. The small dose-range consisted of 20 nl volumes of 50, 75 and 
      100 micromolar (microM) solutions (i.e. 1, 1.5 and 2 pmole in 20 nl, 
      respectively). The larger dose-range consisted of 20 nl volumes of 2.5, 25, 40 
      and 50 millimolar (mM) solutions (i.e. 0.05, 0.5, 0.8 and 1 nmole in 20 nl, 
      respectively). Injections of small doses of NE (1-2 pmole) into the IML increased 
      heart rate (HR); intravenous injections of these doses did not alter either blood 
      pressure (BP) or HR. Larger doses of NE (0.05-1 nmole) elicited a decrease in HR; 
      intravenous injections of these doses increased HR and BP. Maximum increase in HR 
      was produced by injections of 1.5 pmole of NE into the IML; this effect was 
      blocked by prior injections of prazosin (an alpha 1 adrenergic receptor 
      antagonist; 50 pmole) but not idazoxan (an alpha 2 adrenergic receptor blocker; 
      10 pmole) into the IML. Maximum decrease in HR was elicited by injections of 0.8 
      nmole of NE into the IML; this effect was blocked by idazoxan (10 pmole) but not 
      prazosin (50 pmole). Microinjections of idazoxan (10 pmole) alone increased HR 
      while prazosin (50 pmole) alone was ineffective. Intravenous injections of 
      chlorisondamine (a ganglion blocker) blocked the increase in HR elicited by 
      injections of 1.5 pmole of NE into the IML.(ABSTRACT TRUNCATED AT 250 WORDS)
FAU - Sundaram, K
AU  - Sundaram K
AD  - Section of Neurosurgery, University of Medicine and Dentistry of New Jersey 
      Medical School, Newark 07103.
FAU - Murugaian, J
AU  - Murugaian J
FAU - Sapru, H
AU  - Sapru H
LA  - eng
GR  - HL24347/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - Netherlands
TA  - Brain Res
JT  - Brain research
JID - 0045503
RN  - 0 (Adrenergic alpha-Antagonists)
RN  - 0 (Dioxanes)
RN  - X4W3ENH1CV (Norepinephrine)
RN  - XM03YJ541D (Prazosin)
RN  - Y310PA316B (Idazoxan)
SB  - IM
MH  - Adrenergic alpha-Antagonists/pharmacology
MH  - Animals
MH  - Bradycardia/chemically induced
MH  - Dioxanes/pharmacology
MH  - Heart/innervation/*physiology
MH  - Heart Rate/physiology
MH  - Idazoxan
MH  - Male
MH  - Microinjections
MH  - Norepinephrine/administration & dosage/*pharmacology
MH  - Prazosin/pharmacology
MH  - Rats
MH  - Rats, Inbred Strains
MH  - Spinal Cord/drug effects/*physiology
MH  - Sympathetic Nervous System/drug effects/*physiology
MH  - Tachycardia/chemically induced
EDAT- 1991/03/29 00:00
MHDA- 1991/03/29 00:01
CRDT- 1991/03/29 00:00
PHST- 1991/03/29 00:00 [pubmed]
PHST- 1991/03/29 00:01 [medline]
PHST- 1991/03/29 00:00 [entrez]
AID - 0006-8993(91)90058-4 [pii]
AID - 10.1016/0006-8993(91)90058-4 [doi]
PST - ppublish
SO  - Brain Res. 1991 Mar 29;544(2):227-34. doi: 10.1016/0006-8993(91)90058-4.