Long-term administration of the "Liuwei Dihuang Fufang" (Rehmannia and Six Herbs Compound) by oral route to mice did not alter the vitamin C and cholesterol contents in the adrenal glands or affect the eosinophil count in the peripheral blood (1g). Acute experiments on rabbits showed that given singly or with one or two other medicines by intragastric administration at five times the human dose (Radix Rehmanniae Crudae 3 g/kg, Rhizoma Amemarrhena 0.9 g/kg, licorice 0.9 g/kg) antagonized the inhibitory action of dexamethasone on the pituitary-adrenal system, thereby increasing plasma corticosterone. The clinical diurnal dexamethasone on the early morning cortisol secretion peak was definely antagonized by the "Zi Yin Xie Huo Fu Yao Fang" (Vital Energy Nourishing and Sthenic Heat Purgative Compound), given as a decoction or syrup, (Rehmanniae Crudae 30g, Rhizoma Anemarrhena 9g, licorice 9g) given in 2 doses.

When slices of rabbit liver were incubated with the crude extract of the uncured herb (corresponding to 8 mg of crude drug), the latter prevented the reduction of the double bond between the fourth and fifth carbon atoms and of the ketone group of the third carbon, and also the degradation of the hydroxyl group of seventeenth and twenty-first carbon and ketone group of twentieth carbon of the side chain of cortisol A ring. Consequently, it delayed the catabolic effect of hepatic cells on cortisol. When the uncured herb was used simultaneously with exogenous adrenocortical hormones, plasma cortisol could still be kept at nearly normal level. The mechanism was believed to be a kind of competitive effect which influenced the binding of cortical hormone to the hepatocellular receptor and affected the uptake of corticosteroid hormone by the liver cells, thereby slowing down the catabolism of cortisol

The 100% injection of the uncured herb given by intraperitoneal injection 1 ml daily for 6 days, could mitigate platelet damage caused by irradiation with 600 rad and hasten the normalisation of platelet count

The decoction of the herb protected mice against experimental toxic hepatitis induced by carbon tetrachloride, thus preventing the decrease of liver glycogen

Early reports claimed that the alcohol extract of the herb (species not given) injected subcutaneously at 2 g/kg, or given intragastrically at 4 g/kg to rabbits, lowered blood glucose. The result obtained from the injection was more significant; lowest blood glucose level was reached 4 hours after medication. Subcutaneous injection of the alcohol extract to rabbits also suppressed the prolonged hyperglycemic action elicited by the carbohydrates contained in the root of Codonopsis pilosula. Intramuscular injection of the same preparation at the dose of 20 g also inhibited and prevented epinephrine-induced hyperglycemia in rabbits However, other studies reported that the aqueous or alcohol extract of the herb could only lower the blood glucose of normal rabbits and was ineffective in hyperglycemia due to epinephrine Asimilar hypoglycemic effect could also be achieved by subcutaneous injection of reimannin to rabbits at 0.5 g/ kg The herb, used singly, had a more significant hypoglycemic action than the root of Pueraria lobata. The action of "Bawei Dihuang Wan" (Rehmannia and Eight Herbs Pill) was not stronger than that of the herb used alone H owever, other studies showed that the herb had no effect on the normal blood glucose level of rabbits This view was confirmed by recent investigations, i.e., the estract of its decoction or the alcohol extract at the dose of 6 g/kg had no effect on tbe normal blood glucose measurements of rabbits within 6 hours of medication. The same preparations given to rats by subcutaneous injection at the dose of 20 g/kg also failed to antagonize epinephrine-induced hyperglycemia. However, it was also noted that blood glucose level was increased in rats following intragastric administration of the extract of the decoction, which might be due to the large amount of carbohydrates contained in the decoction it was also shown to effect the hypoglycemic activity in spontaneously diabetic mice

The 0.1 and 0.5% extract of the herb in Ringer's solution perfused into isolated frog hearts did not produce a marked effect, but a significant cardiotonic action was elicited when the concentration was increased to 1%; this effect was especially prominent in weak hearts. The concentration of 2-5% was toxic Another investigation proved that the 2-3% decoction or tincture of the herb weakened the contractility of the isolated toad heart, reducing the stroke volume, decreasing the heart rate, and even eliciting conduction block or ventricular arrest The perfusion experiment on isolated rabbit hearts showed that the uncured herb at 0.2-1.0 g decreased coronary flow, but did not affect cardiac contraction.

The moderate dose of 0.5 g and the high dose 1.0 g decreased heart rate However, a recent report claims that the 0.33% alcohol extract of the uncured herb perfused into rabbit hearts could increase coronary flow, though it decreased heart rate. In experiment with 86Rb, it was also demonstrated that intraperitoneal injection of the fluidextract of dried decoction into mice at 20 g/kg significantly increased myocardial blood flow Perfusion of the 1-3% of the herb into the blood vessels of toad limbs by intravenous infusion caused vasoconstriction, whereas the 5% extract caused vasodilation Elevation of blood pressure was observed in anesthetized dogs and rabbits given the intravenous injection of the herb extract, but no pressor effect was seen in decerebrated dogs. The pressor action of the herb is therefore thought to be related to a central mechanism Recently, it has been reported that intravenous injection of the decoction or alcohol extract to anesthetized dogs at 0.8 g/kg elicited a hypotensive effect, which when repeated induced rapid development of tolerance

The yellow, needle-shaped crystal obtained from the ethanol extract shortened the coagulation time in rabbits, whereas the effect achieved with the decoction was insignificant. Intraperitoneal injection of the decoction or alcohol extract at 10 g/ kg and oral administration of the charred herb shortened the bleeding time in mice with tail wounds.

Intravenous injection of the herb extract to anesthetized dogs increased the urine output per unit time; the action mechanism probably related to the cardiotonic action and dilation of renal arteries However, a recent report failed to prove the presumed diuretic action of the decoction and alcohol extract in rats The Rehmannia and Six Herbs Compound (Rhizoma Rehmanniae Praeparata, Fr.uctus Corni, Rhizoma Dioscorea, Cortex Moutan, Rhizoma Alimatis, and Poria in proportion of 8:4:4:3:3:3 prepared as decoction), given to rats with renal hypertension at the dose of 1.5 g/kg daily for 6 days per week, significantly lowered blood pressure, improved renal.function and decreased the mortality rate of the animals

Formaldehyde-induced swelling of rat paws subsided after intragastric administration of the decoction or alcohol extract at 10 g/kg daily for 5 days However, recent reports claimed that only the decoction had such action, whereas the action of the alcohol extract was insignificant

In vitro experiments showed that the aqueous extract inhibited the growth of many kinds of fungi such as Mentagrophyton, Microsporum gypseum and audouini.

Oral administration or intraperitoneal injection of the decoction or the alcohol extract at the dose of 10 g/kg potentiated the hypnotic effect of pentobarbital sodium. Intraperitoneal injection of the decoction or alcohol extract at 20 g/ kg significantly protected mice from hypobaric hypoxia

The decoction or the alcohol extract given to mice intragastrically at the dose of 60 g/kg daily for 3 days caused no deaths or adverse effects during one week of observation. The same agents given to rats by the same route at 18 g/kg did not produce any significant changes in the animals behavior, body onload="highlight();" weight, serum nonprotein nitrogen and SGPT, or any significant lesions in the hepatic and renal tissues during 1.5 month s observationo

Intermittent treatment of 12 cases of rheumatic arthritis and 11 cases of rheumatoid arthritis with the herb decoction produced remarkable therapeutic effects in most patients, evidenced by abatement of joint pain, subsidence of swelling, improvement of joint movement, and normalisation of erythrocyte sedimentation rate. The herb also improved the general symptoms of bronchial asthma and urticaria. In a minority of patients, mild edema developed following the medication, a reaction which is similar to that induced by adrenocortical hormones

Fifty cases were treated with daily intramuscular injection of 2 ampoules of the herb preparation (each ampoule contained 12 g of the uncured herb 12 g, and the root and rhizome of Glycyrrhiza uralensis 6 g), One course lasted 10 days. Forty-one cases achieved improvement in symptoms and signs, and almost normal liver function. In particular, there was a significant reduction of SGPT. Neither local nor systemic adverse effects were seen. Ten other cases who took the decoction of the herb and the root and rhizome of G. uralensis also had beneficial effects.

The decoction of the cured herb was administered to 62 hypertensive cases at the dose of 30-50 g daily for 2 weeks. Blood pressure, serum cholesterol and triglycerides were all reduced, while the cerebral flow and ECG were also improved.

Optimal effects were achieved by intermittent oral treatment of the decoction of the uncured herb in eczema and neurodermatitis. Dosage: 90 g daily.

The side effects of the herb are mild. A minority of patients may develop diarrhea, abdominal pain, dizziness, fatigue, and palpitation, which disappear spontaneously within a few days.

Except those noted, all references come from Weng Weiliang, et al., Clinical Chinese materia medica, Henan Science & Technology Press, 1998