$httpClient = new Zend_Http_Client('http://..../');
// request via post
$response = $httpClient->request(Zend_Http_Client::POST);
// or get
$response = $httpClient->request(Zend_Http_Client::GET);

However the interesting and useful thing is that you can perform authenticated requests:

$httpClient = new Zend_Http_Client('http://username:password@example.com/');
// or define it later
$httpClient = new Zend_Http_Client('http://example.com/');
$httpClient->setAuth('username', 'password');

That’s an opportunity to send/receive authenticated POST requests.

$httpClient = new Zend_Http_Client('http://username:password@example.com/');
// now post
$httpClient->request(Zend_Http_Client::POST);