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Valproic Acid Experiments with valproic acid have shown that it causes identical brain conditions as in autism (Rodier et al, 1997; 1996). The events involved are related to the time of neural tube closure. In the rat neural tube closure day occurs on day 11.5 of gestation, this mean that fetus is yet dependent on maternal thyroid status. In humans, Stromland et al reported in 1994 that the rate of autism was 33% in people exposed to thalidomide between the 20th to 24th days of gestation, and 0% in cases exposed at other times. The neural tube is the progenitor of the central nervous system (CNS).
Neural tube closure and development is regulated by thyroid hormones (Kraft et al, 1994; Flamant, 1998). In one study checking on the effects of valproic acid on thyroid hormones, baseline serum T4 and TSH concentrations were unaffected by valproic acid administration while serum T3 concentrations fell in all volunteers, resulting in Low Free T3 (Elias et al, 1981). This study was done on adults. In children, an increase in TSH levels was particularly marked in valproate-treated children, accounting for 26% of patients with subclinical hypothyroidism (Eiris-Punal et al, 1999). See also: Thalidomide [SAME EFFECTS] See also - Rodier Patent: US 6,228,582 (May 2001) ==================================== ========= Eiris-Punal J, Del Rio-Garma M, Del Rio-Garma MC, Lojo-Rocamonde S, Novo-Rodriguez I, Castro-Gago M - "Long-term treatment of children with epilepsy with valproate or carbamazepine may cause subclinical hypothyroidism" Epilepsia 40(12):1761-6 (1999) http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=10612341&form=6&db=m&Dopt=r Elias AN, Valenta LJ, Szekeres AV, Grossman M - "Effect of FDA Alert http://www.mayohealth.org/mayo/0003/htm/thalidomide_sb.htm (also: Thalomid capsules (thalidomide) prescription product insert/Celgene Corp, Warren, NJ) Flamant F, Samarut J - "Involvement of thyroid hormone and its alpha receptor in avian neurulation" Dev Biol 197(1):1-11 (1998) http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=9578614&form=6&db=m&Dopt=r Kraft JC, Willhite CC, Juchau MR - "Embryogenesis in cultured whole rat embryos after combined exposures to 3,3',5-triiodo-L-thyronine (T3) plus all-trans-retinoic acid and to T3 plus 9-cis-retinoic acid" J Craniofac Genet Dev Biol 14(2):75-86 (1994) http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=8071425&form=6&db=m&Dopt=r Rodier PM, Ingram JL, Tisdale B, Croog VJ -"Linking etiologies in humans and animal models: studies of autism" Reprod Toxicol 11(2-3):417-22 (1997) http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=9100317&form=6&db=m&Dopt=r Rodier PM, Ingram JL, Tisdale B, Nelson S, Romano J - "Embryological origin for autism: developmental anomalies of the cranial nerve motor nuclei" J Comp Neurol 370(2):247-61 (1996) Stromland K, Nordin V, Miller M, Akerstrom B, Gillberg C - “Autism in thalidomide embryopathy: a population study” Dev Med Child Neurol 36(4):351-6 (1994) See also: Thalidomide
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