Effects of Different Refined Carbohydrates on the Blood Pressure of SH and WKY Rats

Abstract

SummaryIt is generally accepted that ingestion of sucrose in large quantities elevates blood pressure (BP). Less certain is whether starch and other refined carbohydrates (CHO) have similar effects. Using spontaneously hypertensive rats (SHR) and normotensive control rats (WKY), we show that glucose, fructose, and starch fed to rats either in solution or in dry form elevate BP to a similar degree as sucrose. The changes in BP brought on by various refined CHO were greater in SHR than in WKY. The elevations did not consistently correlate with differences in body weight, amount of dry matter or fluid intake, the quantities of sodium and potassium ingested, or to changes in the various blood chemistries examined. We conclude that other refined CHO (glucose, fructose, and starch) like sucrose raise BP significantly. This effect on BP is rapid (within days) and reversible, at least to some extent.Key Words: carbohydrates, effects on blood pressure, spontaneously hypertensive rats, effect of CHO, macronutrients Excess ingestion of sucrose, a disaccharide of glucose and fructose, elevates blood pressure (BP) in rats [1]. However, it is uncertain whether simple carbohydrates (CHO) other than sucrose cause similar BP increases. Because previous studies have been inconsistent, glucose, fructose, and starch individually cannot be conclusively implicated in a BP response. For example, Hall and Hall [2] found that addition of glucose to a saline drinking solution elevates BP but was significantly less hypertensive than the combination of sucrose plus saline. Honey, which is composed of fructose, did not elevate BP when added to saline. Beebe

Astaxanthin lowers blood pressure and lessens the activity of the renin-angiotensin system in Zucker Fatty Rats

“…As in many previous studies, an instrument from Narco Biosciences (Houston, TX) was used (Preuss & Preuss, 1980;Preuss et al, 1988). This allowed us to rapidly measure SBP with a beeper sound system.…”

Blood pressure lowering effects of niacin-bound chromium(III) (NBC) in sucrose-fed rats: Renin–angiotensin system

“…Later, however, it was discovered in rats that ingestion of sugars alone (sucrose, fructose, or glucose) without added salt provoked a significant elevation of blood pressure [1,3]. Of further interest, excess sugar consumption and insulin resistance have also been associated with many manifestations of the metabolic syndrome such as obesity, type 2 diabetes, and various dyslipidemias [21][22][23][24].…”

“…At the initiation of study, we compared two methods to determine the indirect blood pressure of rats, because our original method measured only SBP [1,3]. The newer method also provides diastolic and mean pressure readings as well as cardiac rates.…”

“…As in many of our previous studies, we used an instrument from Narco Biosciences (Houston, TX) [1,3]. This allowed us to rapidly measure SBP with a beeper sound system.…”

“…Ingestion of large quantities of sucrose and/or other sugars like fructose and glucose in certain strains of rats induces systolic blood pressure (SBP) elevations and other metabolic disorders [1][2][3]. The exact pathological mechanism(s) behind sugar-induced hypertension are uncertain, but the elevated SBP may relate to a number of perturbed underlying regulating mechanisms including augmented catecholamine levels [4], disturbed vasodilatory function via disturbances in NO signaling in blood vessels [5], alterations in fluid and electrolyte balance [6], and disturbances in the renin-angiotensin system (RAS) manifested by elevated circulating levels of angiotensin-2 [7].…”