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Hypertension is a frequent finding in patients with chronic kidney disease. Whether primary or secondary to renal disease, hypertension remains an important risk factory for the progression of chronic kidney disease and the occurrence of cardiovascular events. The objective of this paper is to review different treatment strategies in hypertensive CKD patients, with the exclusion of patients with renal replacement therapy such as dialysis or renal transplantation.

The dynamic regulation of neurotransmitters and their receptors is an important component of the process of coping and stress adaptation. Among the central neurochemical systems, CRF and the renin-angiotensin may represent major modulatory systems involved in the adaptation of an organism to chronic stress, balancing the response demands that the stressor places on the central nervous system with the potentially detrimental effects that a sustained stress response may produce. As such, the study of these two systems with respect to their neurotransmitters and receptors will allow us to achieve a better perspective on the mechanisms responsible for effective short-term coping with stress as well as long-term adaptation and restoration in response to chronic or repeated stress. It will then be possible to verify the level of activation of different components of the central pathways involved in the mediation of stress responses in rat strains which develop hypertension following chronic exposure to stress. The primary objective of the present paper is to review some facts on the contribution of the central renin-angiotensin system on the regulatory mechanisms involved in the mediation of physiological responses to stress and on the involvement of these neurons in the CNS adaptation in rat strains that are developing hypertension when chronically exposed to stress. Neurons that are expressing angiotensin-receptors may be important in the short-term adaptation to stress by potentiating sympathoadrenal and/or hypophyseo-pituitary-adrenal responses. These same neurons may also participate in long-term stress-adaptation by altering gene expression of their angiotensin receptors. Moreover, these processes represent potential points of dysregulation in the case of extreme, repeated or prolonged stress, and thus in the development of stress-related pathological states such as hypertension and heart diseases.

The renin-angiotensin system is involved in the control of sodium and water balance, mitogenesis and the regulation of vascular tone as well as of the activity of the sympathetic nervous system. Many of these effects may be regulated at a local level by independent tissue renin-angiotensin systems. The renin-angiotensin and adrenergic nervous systems are cross-regulated by interactive compensatory mechanisms. Therefore, the activation of one of these systems induces the activation or induction of the other leading to a co-amplification of cellular mechanisms, for instance resulting in the facilitation of sympathetic neurotransmission. This paper describes the interactions between these systems in the central nervous system and at pre- and postsynaptic sites of the nerve endings in cardiovascular tissues. Since these systems are cross-regulated, the inhibition of one would attenuate the activity of the other. The drugs that inhibit specifically the various components of the renin-angiotensin system have proved powerful tools for studies of the physiology of this system as well as for the treatment of hypertension and heart failure.

Angiotensin converting-enzyme inhibitors cross the placenta and modify the maternal, foetal and utero-placental renin-angiotensin system. Eight cases of pregnancy in women taking captopril have been published, 7 other cases being reported in this review paper. There were one spontaneous and 2 therapeutic abortions, one of which disclosed a malformation of uncertain diagnosis and imputation. One intrauterine death at 28 weeks was probably due to the severity of the maternal disease. Two children born to mothers also treated with frusemide died of neonatal anuria. Delivery or caesarean section occurred before term in 8 cases, and there were 3 cases of neonatal respiratory distress with a favourable outcome. Finally, one mother gave birth at term to twins of normal weight. The cases with respiratory distress can be attributed to the mother's hypertension, to prematurity and/or to concomitant treatment with beta-blockers, while the cases with anuria seem to be due to inhibition of the effects of angiotensin on renal haemodynamics, with salt depression as a possible aggravating factor. Treatment with angiotensin converting enzyme inhibitors does not seem to warrant therapeutic abortion. However, these drugs are contra-indicated in pregnancy and should only be given to women wishing to become pregnant if they present with resistant and dangerous arterial hypertension. A programme of pharmacovigilance is being set up to follow up such pregnancies.