RESUMEN
Since Diabetes Control and Complications Trial (DCCT), intensive therapy has been directed at achieving glucose and glycosylated hemoglobin (HbA1c) values as close to normal as possible regarding safety issues. However, hyperglycemia (especially postprandial hyperglycemia) and hypoglicemia continue to be problematic in the management of type 1 diabetes. The objective of associating other drugs to insulin therapy is to achieve better metabolic control lowering postprandial blood glucose levels. Adjunctive therapies can be divided in four categories based on their mechanism of action: enhancement of insulin action (e.g. the biguanides and thiazolidinediones), alteration of gastrointestinal nutrient delivery (e.g. acarbose and amylin) and other targets of action (e.g. pirenzepine, insulin-like growth factor I and glucagon-like peptide-1). Many of these agents have been found to be effective in short-term studies with decreases in HbA1c of 0.5-1%, lowering postprandial blood glucose levels and decreasing daily insulin doses.
Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hemoglobina Glucada/metabolismo , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Tiazolidinedionas/uso terapéutico , Acarbosa/metabolismo , Acarbosa/uso terapéutico , Amiloide/metabolismo , Amiloide/uso terapéutico , Diabetes Mellitus Tipo 1/metabolismo , Quimioterapia Combinada , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/metabolismo , Péptido 1 Similar al Glucagón/análogos & derivados , Péptido 1 Similar al Glucagón/metabolismo , Péptido 1 Similar al Glucagón/uso terapéutico , Humanos , Hiperglucemia/tratamiento farmacológico , Hiperglucemia/metabolismo , Hipoglucemia/tratamiento farmacológico , Incretinas/metabolismo , Incretinas/uso terapéutico , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Polipéptido Amiloide de los Islotes Pancreáticos , Metformina/uso terapéutico , Antagonistas Muscarínicos/metabolismo , Antagonistas Muscarínicos/uso terapéutico , Pirenzepina/metabolismo , Pirenzepina/uso terapéutico , Periodo PosprandialRESUMEN
Desde o Diabetes Control and Complications Trial (DCCT), a terapia insulínica intensiva tem sido direcionada para alcançar valores de glicemia e hemoglobina glicada (HbA1c) tão próximos do normal quanto a segurança permita. Entretanto, a hiperglicemia (especialmente a hiperglicemia pós-prandial) e a hipoglicemia continuam a ser um problema no manejo do diabetes tipo 1. O objetivo de associar outras drogas à terapia insulínica é diminuir a glicemia pós-prandial. A terapia adjunta pode ser dividida em três grupos, conforme seu mecanismo de ação: 1. Aumento da ação da insulina (metformina e tiazolidinedionas); 2. Alteração da liberação de nutrientes no trato gastrintestinal (acarbose e amilina); 3. Outros modos de ação [pirenzepina, fator de crescimento insulina-símile (IGF-1) e peptídeo semelhante ao glucagon 1 (GLP-1). Muitos desses agentes mostraram, em estudos de curto prazo, diminuição de 0,5 por cento a 1 por cento na HbA1c, diminuir a hiperglicemia pós-prandial e as doses diárias de insulina.
Since Diabetes Control and Complications Trial (DCCT), intensive therapy has been directed at achieving glucose and glycosylated hemoglobin (HbA1c) values as close to normal as possible regarding safety issues. However, hyperglycemia (especially postprandial hyperglycemia) and hypoglicemia continue to be problematic in the management of type 1 diabetes. The objective of associating other drugs to insulin therapy is to achieve better metabolic control lowering postprandial blood glucose levels. Adjunctive therapies can be divided in four categories based on their mechanism of action: enhancement of insulin action (e.g. the biguanides and thiazolidinediones), alteration of gastrointestinal nutrient delivery (e.g. acarbose and amylin) and other targets of action (e.g. pirenzepine, insulin-like growth factor I and glucagon-like peptide-1). Many of these agents have been found to be effective in short-term studies with decreases in HbA1c of 0.5-1 percent, lowering postprandial blood glucose levels and decreasing daily insulin doses.
Asunto(s)
Humanos , Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hemoglobina Glucada/metabolismo , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Tiazolidinedionas/uso terapéutico , Acarbosa/metabolismo , Acarbosa/uso terapéutico , Amiloide/metabolismo , Amiloide/uso terapéutico , Quimioterapia Combinada , Diabetes Mellitus Tipo 1/metabolismo , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/metabolismo , Péptido 1 Similar al Glucagón/análogos & derivados , Péptido 1 Similar al Glucagón/metabolismo , Péptido 1 Similar al Glucagón/uso terapéutico , Hiperglucemia/tratamiento farmacológico , Hiperglucemia/metabolismo , Hipoglucemia/tratamiento farmacológico , Incretinas/metabolismo , Incretinas/uso terapéutico , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Metformina/uso terapéutico , Antagonistas Muscarínicos/metabolismo , Antagonistas Muscarínicos/uso terapéutico , Periodo Posprandial , Pirenzepina/metabolismo , Pirenzepina/uso terapéuticoRESUMEN
The distribution and down-regulation of the muscarinic acetylcholine receptor (mAChR) were studied in dissociated cells from right (RCC) and left (LCC) cerebral cortex. For this purpose [3H]quinuclidinyl benzilate (QNB) and [3H]pirenzepine (Pz), two muscarinic antagonists, were used. The mAChR binding sites detected with [3H]QNB were asymmetrically distributed between the two hemispheres, the majority being found in the RCC. Asymmetry was also evident in the distribution of the mAChR subtypes (M1 and M2) detected with [3H]Pz. Under basal conditions the RCC had roughly 50% more M1 subtype than the LCC. The pharmacological and kinetic parameters were similar for both antagonists in RCC and LCC, indicating that the observed lateralization was due to a different density of the receptor rather than to different kinetics of binding of the two radioligands. After sustained stimulation with the agonist carbamoylcholine, the receptor sites detected with [3H]Pz, i.e. the M1 subtype of mAChR, decreased at a higher rate in the RCC (44%) than in the LCC (25% of controls), demonstrating that the down-regulation process is more active in the right than in the left cortex, and thus implying that there is better coupling between the stimulated mAChR and its effector system in the former.