A burst of insulin secretion normally occurs after ingestion of a meal in response to transient increase in the levels of circullating glucose and amino acids. In the post operative period, low, basal levels of circulating insulin are maintained through beta cell secretion. However type one diabetes has virtually no functional beta cells [2].

Treatment: Type 1 diabetic must rely on exogenous(injected) insulin in order tp control hyperglycemia, maintain acceptable levels of glycosylated hemoglobin (HbA₁C) and avoid ketoacedosis. The goal in administering insulin to type 1 diabetic is to maintain blood glucose concentrations as close to normal as possible and to avoid wide swings in blood glucose level that may contribute to long term complications.

Most diabetic are in this category, metabolic alterations observed are milder than those discribed for IDDM [e.g NIDDM patients typically are not ketotic], though long term clinical consequences can be just as devastating e.g. vascular complications and subsequent infections can lead to amputation of lower limbs [3].

In NIDDM pancrease retains some beta cell function, resulting in variable insulin levels that are insufficient to maintain glucose homeostatis. Patients with type 2 diabetes are often obese [4].

Diabetes is freequently accompained by target organ insulin resistence that limits responsiveness to both endogenous and exogenous insulin. In some cases insulin resistence is due to a decreased number of mutations of insulin receptors [5].

The goal in treating type 2 diabetes is to maintain blood glucose concentrations with normal limits and to prevent the development of long term complications of thhe diseases. Weight reduction, exercise and dietory modification decrease insulin resistence and correct the hyperglycemia of type 2 diabetes in some pateints. Oral hypoglycemic agents and insulin therapy may requiered to acheive satisfactory serum glucose levels [6-12].

Scientific name : Vanda tessellate(Roxb)Hook.

Kingdom :Plantae

(unranked): Angiospermis

(unranked):Monocots

Order :Asparagales

Family :Orchidaceae

Subfamily :Ebidendroideae

Tribe :Vandeae

Genus :Vanda

Species: V.tessellata

The plant vanda tessellate collected from western ghat, gobi, erode. after collection the plant was washed thoroughly with running tap water, cut into small pieces and shade dried. The dried material was then pulverized separately into coarse powder by a mechanical grinder. The resulting powder was preserved in the department for further study.

Adult albino rats (wister strain) of either sex with weighing 150-180gm were used. The animals were maintained on the suitable nutritional and environmental condition throughout the experiment. The animals were housed in polypropylene cages with paddy house bedding under standard laboratory condition for an acclimatization periods of 7 days prior to performing the experiment. The animals had access to laboratory chow and water ad libitum.

Hyperglcemia was induced by a single intra peritonial injection of freshly prepared aqueous solution of alloxan monohydrate (SD fine chemicals Pvt.Ltd., Biosar) 150mg/kg, to overnight fasted rats. Control rats recieves similar volume of vehicle, normal saline(2ml/kg body weight) alone. Animals that did not develope hyperglycemia after 48 hrs of alloxan injection were rejected and new animals were used. Immediately after confirmation of diabetes, rats were classified into six groups of six rats each. Group I received normal saline and served as control. Group II treated with alloxan monohydrate 150mg/kg served as diabetic control. Group III&IV treated WHOLE plant methanol extract (100mg/kg &200mg/kg) respectively. Group V treated with glibenclamide(5mg/kg)served as reference standard. Treatment continued for 21 consecutive days. Before the treatment (0day), and at the end of 7^th and 21^th day plasma levels were estimed using the glucose oxidase method. The results were analysed byy student ‘t’ test.

Table no.1 : Antihyperglycemic activity of vanda tesselleta on control and alloxan induced diabetic rats

The effect of vanda tessellate(roxb)hook plant extract on blood sugar level of alloxan induced diabetic rats was given on table 1. Oral administration of vanda tessellate (roxb) hook whole plant extract (100 & 200mg/kg) was evaluated for its anti-diabetic activity against alloxan induced diabetes in rats. Blood sugar levels were determined on 1^st,7^th,14^th and 21^th day after the test drug administration. The doses 100 mg/kg of vanda tessellate (roxb)hook whole plant extract showed significant (P<0.01) decrease in the blood sugar level in alloxan induced diabetic rats. The effects were comparable with the the effect produced by the glibinclamide treated group.

Graph shows the effect of methanol extract of vanda tessellate(roxb)hook on blood glucose level of normal, diabetic induced and drug treated rats as different week intervals treatment blood glucose(mg/dl).