Passar esse código PHP para C#

<?php
$curl = curl_init();

curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($curl, CURLOPT_POST, true);
curl_setopt($curl, CURLOPT_URL, 'https://api-3t.sandbox.paypal.com/nvp');

curl_setopt($curl, CURLOPT_POSTFIELDS, http_build_query(array( 'USER' => 'usuario_da_api', 'PWD' => '123412432134', 'SIGNATURE' => 'assinatura.da.api',

'METHOD' => 'UpdateRecurringPaymentsProfile',
'VERSION' => '108',
'PROFILEID' => 'I-FYYMDB55ADSH',

'NOTE' => 'Uma nota opcional, explicando o motivo da mudança',

 'AMT' => 60,
 'CURRENCYCODE' => 'BRL'
)));

$response = curl_exec($curl);

curl_close($curl);

$nvp = array();

if (preg_match_all('/(?<name>[^\=]+)\=(?<value>[^&]+)&?/', $response, $matches)) {
 foreach ($matches['name'] as $offset => $name) {
 $nvp[$name] = urldecode($matches['value'][$offset]);
 }
}

print_r($nvp);

Galera, como faz para passar esse código PHP do Paypal para C#?