Hypertension, atherosclerosis, stress and lactic acid

Hypertension is considered as an important risk factor for the development of atherosclerosis, with these processes sharing some common mechanisms. The endothelium is placed usually as a probable central focus for the effects in both diseases, with evidences leading to the postulation that hypertension predispose and accelerate atherosclerosis. Coronary myocardial-disease is the main death cause in hypertensive patients.
Stress is one of the suggested factors for the hypertension origin and its reduction may help to reduce an elevated blood pressure. Coincidently stress can also contribute for the development and subsequent complications of atherosclerosis what is evidenced in many studies (1).
The key mechanism according the acidity theory of atherosclerosis (1) as the triggering factor for hypertension and atherosclerosis, is the elevation of the lactic acid production in blood. It is interesting to note that lactic acid in blood plasma can have a significant elevation during stress situations , serving as an indicator of stress levels (2, 3). Also, high carbohydrate diet may increase significantly the activity of serum lactate dehydrogenase (4,5). On the other side the concentration of lactic acid in both venous and arterial blood may be significantly elevated in hypertension as showed a study published 45 years ago (6), which results were confirmed recently by the Atherosclerosis Risk in Communities (ARIC) Carotid MRI Study, that measured plasma lactate in 2066 older adults. This study came to the conclusion that high plasma lactate was independently associated with the odds of hypertension (7).
1) Carlos ETB Monteiro, Acidic environment evoked by chronic stress: A novel mechanism to explain atherogenesis. Available from Infarct Combat Project, January 28, 2008 at http://www.infarctcombat.org/AcidityTheory.pdf
2) Sharda S, Gupta SN and Khuteta KP. 1975. Effect on mental stress on intermediate carbohydrate-and lipid-metabolism. Indian J Physiol Pharmacol. Apr-Jun;19(2):86-9.
3) Hall JB, Brown DA. 1979. Plasma glucose and lactic acid alterations in response to a stressful exam. Biol Psychol. May;8(3):179-88.
4) Marshall MW and Iacono JM (1976). Changes in lactate dehydrogenase, LDH isoenzymes, lactate, and pyruvate as a result of feeding low fat diets to healthy men and women. Metabolism. 1976 Feb;25(2):169-78.
5)Yoshimura T, Miyoshi T, et al. (1986). Effect of high carbohydrate diet on serum lactate dehydrogenase isozyme pattern in Japanese young men. Acta Biol Hung. 1986;37(3-4):243-8.
6) F. E. Demartini, P. J. Cannon, W. B. Stason, and J. H. Laragh. 1965. Lactic Acid Metabolism in Hypertensive Patients. Science 11 June, Vol. 148. no. 3676, pp. 1482 – 1484 em http://www.sciencemag.org/cgi/content/abstract/148/3676/1482
7) Abstract 5003: Association of Blood Lactate with Hypertension: The Atherosclerosis Risk in Communities Carotid MRI Study. J Hunter Young; Stephen O Crawford; Frederick L Brancati; Ron C Hoogeveen; Muhammad Amer; Christie M Ballantyne; Maria I Schmidt; Brad C Astor; Josef Coresh, Circulation. 2008;118:S_1129.), http://circ.ahajournals.org/cgi/content/meeting_abstract/118/18_MeetingAbstracts/S_1129-a