Catecholamines, derived from the amino acid tyrosine, produced by
the adrenal glands, which are found on top of the kidneys. are
epinephrine (adrenaline), norepinephrine (noradrenaline) and dopamine.
The hormone are released into the blood during times of physical or
emotional stress.
A. Epinephrine
1. Epinephrine and thyroidism
In the study of measurement of the secretion rate of epinephrine in 6 euthyroid, 6 hyperthyroid, and 6 hypothyroid subjects infused at a constant rate for a one hour period with tritiated epinephrine
(.01 muc/kg/min) (New England Nuclear Inc.), found that plasma
secretion rates averaged 48 +/- 27 mug/kg/day in normal subjects,
compared to 54 +/- 18 mu/kg/day in hyperthyroidism and 43 +/- 20
mug/kg/day in hypothyroidism. Likewise, the mean urinary secretion rate
was 55 +/- 27 mug/kg/day in normal subjects compared to 60 +/- 22
mug/kg/day in hyperthyroidism and 50 +/- 28 mug/kg/day in
hypothyroidism. There is no statistical difference between the values
found in the three groups of subjects (plasma and urine). Therefore,
these results would indicate that the signs and symptoms encountered in
hyperthyroidism are not secondary to a high secretion rate of epinephrine(1).
2. Epinephrine-containing local anesthesia and cardiovascular disease
In the study to examine the safety of epinephrine-containing local anesthesia for use on patients with cardiovascular diseasein twenty-seven patients with cardiovascular disease,
showed that Systolic blood pressure and heart rate increased by 4.1%
and 5.1%, respectively, immediately after the lidocaine-epinephrine
injection. Consequently, rate pressure product increased by 10.0%.
Cardiac index increased by 14.2%, and total peripheral resistance
decreased by approximately 10%. No patient complained of cardiac
symptoms. There were no significant differences in hemodynamic responses
related to the extent of the cardiac functional capacity(2).
3. Propranolol administration epinephrine-stimulated SSRBC adhesion in Sickle red blood cells (SSRBCs) patients
Sickle red blood cells
(SSRBCs) adhere to both endothelial cells (ECs) and the extracellular
matrix. In the study to investigate whether systemically administered
propranolol inhibits SSRBC adhesion and to document the safety of
propranolol in SCD, indicated that Propranolol administration
significantly reduced epinephrine-stimulated
SSRBC adhesion in a dose dependent manner (p = 0.03), with maximum
inhibition achieved at 40 mg. Adverse events were not severe, did not
show dose dependence, and were likely unrelated to drug. No significant
heart rate changes occurred. These results imply that β-blockers may
have a role as antiadhesive therapy for SCD(3).
4. Hormone Epinephrine and sickle cell disease (SCD).
The possible role of
physiologic stress hormones in enhancing adhesion of sickle erythrocytes
(SS RBCs) to endothelial cells (ECs) in sickle cell disease (SCD). In the study of Epinephrine
acts through erythroid signaling pathways to activate sickle cell
adhesion to endothelium via LW-alphavbeta3 interactions, found
that up-regulation of intracellular cyclic adenosine monophosphate
(cAMP)-dependent protein kinase A (PKA) by epinephrine
significantly increased sickle but not normal erythrocyte adhesion to
both primary and immortalized ECs. Inhibition of serine/threonine
phosphatases also enhanced sickle erythrocyte adhesion at least
partially through a PKA-dependent mechanism. Adhesion was mediated
through LW (intercellular adhesion molecule-4 [ICAM-4], CD242) blood
group glycoprotein, and immunoprecipitation studies showed that LW on
sickle but not on normal erythrocytes undergoes increased PKA-dependent
serine phosphorylation as a result of activation(4).
5. Low dose of intravenous (IV) epinephrine and monomorphic ventricular tachycardia (VT) in the setting of coronary artery disease
There is a report of three cases of sustained monomorphic ventricular tachycardia (VT) in the setting of coronary artery disease, resistant to beta-blockers in two patients and to amiodarone in all, successfully terminated by low doses of intravenous (IV) epinephrine. VT was the first manifestation of coronary artery disease
in one patient, whereas the other two patients had a previous history
of myocardial infarction and were recipients of an implantable
cardioverter-defibrillator (ICD). One of these two patients experienced
an arrhythmic storm. All had hemodynamic instability at the time of epinephrine administration(5).
6. Vitamin C and epinephrine
Vitamin C has several well-established roles in physiology including synthesis of collagen, carnitine and epinephrine,
absorption of dietary iron, and mobilization of storage iron for
erythropoeisis. Loss of several of these functions explains the
pathology of scurvy, where defective collagen synthesis and anemia are
major symptoms. Vitamin C deficiency is very common in dialysis patients
and may arise from dialytic vitamin C clearance, restricted intake of
vitamin C-rich foods, and increased vitamin C catabolism in vivo from
inflammation. In the dialysis population, greater vitamin C intake may
be needed for optimal health(6).
7. Epinephrine and cardiac arrest
Epinephrine is widely used in cardiopulmonary resuscitation for out-of-hospital cardiac arrest (OHCA). In the study to evaluate the association between epinephrine use before hospital arrival and short- and long-term mortality in patients with cardiac
arrest, researchers at the Department of Health Services Management and
Policy, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan, showed
that among patients with OHCA in Japan, use of prehospital epinephrine
was significantly associated with increased chance of return of
spontaneous circulation before hospital arrival but decreased chance of
survival and good functional outcomes 1 month after the event(7).
8. Epinephrine in the treatment of anaphylaxis
In the study to review recent literature that impacts the use of epinephrine in the therapy of anaphylaxis, found that the intramuscular route of administration for epinephrine
is superior has now been recognized by the guidelines, and because the
site of choice has been found to be the lateral aspect of the thigh, the
needle used for injection must be long enough to penetrate the vastus
lateralis muscle and outdated EpiPens can usually be administered
safely, and alternative routes of administration, which may be more
acceptable to patients, may be on the horizon as a result of preliminary
studies assessing the administration of sublingual epinephrine by wafer(8).
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Sources
(1) http://www.ncbi.nlm.nih.gov/pubmed/1249180
(2) http://www.ncbi.nlm.nih.gov/pubmed/11740477
(3) http://www.ncbi.nlm.nih.gov/pubmed/23253664
(4) http://www.ncbi.nlm.nih.gov/pubmed/15308566
(5) http://www.ncbi.nlm.nih.gov/pubmed/23110246
(6) http://www.ncbi.nlm.nih.gov/pubmed/23106569
(7) http://www.ncbi.nlm.nih.gov/pubmed/22436956
(8) http://www.ncbi.nlm.nih.gov/pubmed/12865777
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